title: issue with sonar 3.6.1 (not on all servers)
body: <p>I can't get rid of this error - i've tried with a new .m2 repo, and putting Nexus out of service to pull direct from M2 repos...</p>
  
  <p>I'm not really sure where to go here - this does seem to work on another build server, but not a couple others...</p>
  
  <p>Any help is appreciated :)   There was no change, other than upgrading from 3.4.1 to 3.6, and now 3.6.1...</p>
  
  <p>Please advise...</p>
  
  <pre><code>13:55:43,410 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] [13:55:43.410] Install plugins
  13:55:43,603 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] [13:55:43.603] Download sonar-l10n-en-plugin-3.6.1.jar
  13:55:43,622 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] [13:55:43.622] Download sonar-cpd-plugin-3.6.1.jar
  13:55:43,672 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] [13:55:43.671] Download sonar-email-notifications-plugin-3.6.1.jar
  13:55:43,859 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] [13:55:43.859] Download sonar-core-plugin-3.6.1.jar
  13:55:43,868 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] [13:55:43.868] Download sonar-dbcleaner-plugin-3.6.1.jar
  13:55:43,876 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] [13:55:43.876] Download sonar-design-plugin-3.6.1.jar
  13:55:44,100 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] [13:55:44.100] Install JDBC driver
  13:55:44,106 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] [13:55:44.106] Create JDBC datasource for jdbc:mysql://sonarserver:3306/sonar?useUnicode=true&amp;characterEncoding=utf8
  13:55:44,137 [master&gt;run Sonar@buildserver:8810] INFO  - [FATAL ERROR] org.sonar.maven.SonarMojo#execute() caused a linkage error (java.lang.NoClassDefFoundError) and may be out-of-date. Check the realms:
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - [FATAL ERROR] Plugin realm = app0.child-container[org.codehaus.sonar:sonar-maven-plugin:3.6.1]
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[0] = file:/data/quickbuild/.m2/repository/org/codehaus/sonar/sonar-maven-plugin/3.6.1/sonar-maven-plugin-3.6.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[1] = file:/data/quickbuild/.m2/repository/org/apache/maven/shared/maven-dependency-tree/1.2/maven-dependency-tree-1.2.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[2] = file:/data/quickbuild/.m2/repository/org/codehaus/plexus/plexus-utils/1.1/plexus-utils-1.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[3] = file:/data/quickbuild/.m2/repository/org/codehaus/sonar/sonar-batch/3.6.1/sonar-batch-3.6.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[4] = file:/data/quickbuild/.m2/repository/com/akiban/akiban-persistit/3.2.7/akiban-persistit-3.2.7.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[5] = file:/data/quickbuild/.m2/repository/org/slf4j/slf4j-api/1.6.2/slf4j-api-1.6.2.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[6] = file:/data/quickbuild/.m2/repository/org/codehaus/sonar/sonar-core/3.6.1/sonar-core-3.6.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[7] = file:/data/quickbuild/.m2/repository/org/codehaus/sonar/sonar-plugin-api/3.6.1/sonar-plugin-api-3.6.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[8] = file:/data/quickbuild/.m2/repository/org/codehaus/sonar/sonar-check-api/3.6.1/sonar-check-api-3.6.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[9] = file:/data/quickbuild/.m2/repository/org/codehaus/sonar/sonar-colorizer/3.6.1/sonar-colorizer-3.6.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[10] = file:/data/quickbuild/.m2/repository/com/google/guava/guava/10.0.1/guava-10.0.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[11] = file:/data/quickbuild/.m2/repository/com/google/code/findbugs/jsr305/1.3.9/jsr305-1.3.9.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[12] = file:/data/quickbuild/.m2/repository/org/codehaus/sonar/sonar-channel/3.6.1/sonar-channel-3.6.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[13] = file:/data/quickbuild/.m2/repository/commons-io/commons-io/2.0.1/commons-io-2.0.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[14] = file:/data/quickbuild/.m2/repository/org/codehaus/sonar/sonar-duplications/3.6.1/sonar-duplications-3.6.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[15] = file:/data/quickbuild/.m2/repository/org/codehaus/sonar/sonar-graph/3.6.1/sonar-graph-3.6.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[16] = file:/data/quickbuild/.m2/repository/commons-lang/commons-lang/2.6/commons-lang-2.6.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[17] = file:/data/quickbuild/.m2/repository/org/codehaus/sonar/sonar-squid/3.6.1/sonar-squid-3.6.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[18] = file:/data/quickbuild/.m2/repository/org/picocontainer/picocontainer/2.14.3/picocontainer-2.14.3.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[19] = file:/data/quickbuild/.m2/repository/org/hibernate/hibernate-annotations/3.4.0.GA/hibernate-annotations-3.4.0.GA.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[20] = file:/data/quickbuild/.m2/repository/org/hibernate/ejb3-persistence/1.0.2.GA/ejb3-persistence-1.0.2.GA.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[21] = file:/data/quickbuild/.m2/repository/org/hibernate/hibernate-commons-annotations/3.1.0.GA/hibernate-commons-annotations-3.1.0.GA.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[22] = file:/data/quickbuild/.m2/repository/dom4j/dom4j/1.6.1/dom4j-1.6.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[23] = file:/data/quickbuild/.m2/repository/xml-apis/xml-apis/1.3.03/xml-apis-1.3.03.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[24] = file:/data/quickbuild/.m2/repository/commons-configuration/commons-configuration/1.6/commons-configuration-1.6.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[25] = file:/data/quickbuild/.m2/repository/commons-collections/commons-collections/3.2.1/commons-collections-3.2.1.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[26] = file:/data/quickbuild/.m2/repository/commons-digester/commons-digester/1.8/commons-digester-1.8.jar
  13:55:44,138 [master&gt;run Sonar@buildserver:8810] INFO  - urls[27] = file:/data/quickbuild/.m2/repository/commons-beanutils/commons-beanutils/1.8.3/commons-beanutils-1.8.3.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[28] = file:/data/quickbuild/.m2/repository/commons-codec/commons-codec/1.4/commons-codec-1.4.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[29] = file:/data/quickbuild/.m2/repository/jfree/jfreechart/1.0.9/jfreechart-1.0.9.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[30] = file:/data/quickbuild/.m2/repository/jfree/jcommon/1.0.12/jcommon-1.0.12.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[31] = file:/data/quickbuild/.m2/repository/org/slf4j/jcl-over-slf4j/1.6.2/jcl-over-slf4j-1.6.2.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[32] = file:/data/quickbuild/.m2/repository/org/slf4j/log4j-over-slf4j/1.6.2/log4j-over-slf4j-1.6.2.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[33] = file:/data/quickbuild/.m2/repository/com/thoughtworks/xstream/xstream/1.3.1/xstream-1.3.1.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[34] = file:/data/quickbuild/.m2/repository/xpp3/xpp3/1.1.3.3/xpp3-1.1.3.3.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[35] = file:/data/quickbuild/.m2/repository/org/codehaus/woodstox/woodstox-core-lgpl/4.0.4/woodstox-core-lgpl-4.0.4.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[36] = file:/data/quickbuild/.m2/repository/org/codehaus/woodstox/stax2-api/3.0.1/stax2-api-3.0.1.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[37] = file:/data/quickbuild/.m2/repository/stax/stax-api/1.0.1/stax-api-1.0.1.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[38] = file:/data/quickbuild/.m2/repository/org/codehaus/staxmate/staxmate/2.0.0/staxmate-2.0.0.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[39] = file:/data/quickbuild/.m2/repository/xerces/xercesImpl/2.8.1/xercesImpl-2.8.1.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[40] = file:/data/quickbuild/.m2/repository/xalan/xalan/2.7.1/xalan-2.7.1.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[41] = file:/data/quickbuild/.m2/repository/xalan/serializer/2.7.1/serializer-2.7.1.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[42] = file:/data/quickbuild/.m2/repository/org/mybatis/mybatis/3.1.1/mybatis-3.1.1.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[43] = file:/data/quickbuild/.m2/repository/org/codehaus/sonar/sonar-update-center-common/1.6.1/sonar-update-center-common-1.6.1.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[44] = file:/data/quickbuild/.m2/repository/org/codehaus/sonar/sonar-home/3.6.1/sonar-home-3.6.1.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[45] = file:/data/quickbuild/.m2/repository/org/hibernate/hibernate-core/3.3.2.GA/hibernate-core-3.3.2.GA.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[46] = file:/data/quickbuild/.m2/repository/antlr/antlr/2.7.6/antlr-2.7.6.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[47] = file:/data/quickbuild/.m2/repository/org/hibernate/hibernate-entitymanager/3.4.0.GA/hibernate-entitymanager-3.4.0.GA.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[48] = file:/data/quickbuild/.m2/repository/javassist/javassist/3.4.GA/javassist-3.4.GA.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[49] = file:/data/quickbuild/.m2/repository/geronimo-spec/geronimo-spec-jta/1.0-M1/geronimo-spec-jta-1.0-M1.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[50] = file:/data/quickbuild/.m2/repository/commons-dbcp/commons-dbcp/1.4/commons-dbcp-1.4.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[51] = file:/data/quickbuild/.m2/repository/org/codehaus/plexus/plexus-classworlds/2.2.3/plexus-classworlds-2.2.3.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[52] = file:/data/quickbuild/.m2/repository/com/googlecode/json-simple/json-simple/1.1.1/json-simple-1.1.1.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[53] = file:/data/quickbuild/.m2/repository/com/tinkerpop/blueprints/blueprints-core/2.2.0/blueprints-core-2.2.0.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[54] = file:/data/quickbuild/.m2/repository/ch/qos/logback/logback-classic/0.9.30/logback-classic-0.9.30.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[55] = file:/data/quickbuild/.m2/repository/ch/qos/logback/logback-core/0.9.30/logback-core-0.9.30.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[56] = file:/data/quickbuild/.m2/repository/org/codehaus/sonar/sonar-deprecated/3.6.1/sonar-deprecated-3.6.1.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[57] = file:/data/quickbuild/.m2/repository/org/codehaus/sonar/sonar-java-api/3.6.1/sonar-java-api-3.6.1.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[58] = file:/data/quickbuild/.m2/repository/com/google/code/gson/gson/2.2.4/gson-2.2.4.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[59] = file:/data/quickbuild/.m2/repository/com/h2database/h2/1.3.167/h2-1.3.167.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - [FATAL ERROR] Container realm = plexus.core
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[0] = file:/data/tools/apache-maven-2.2.1/lib/maven-2.2.1-uber.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - [FATAL ERROR] org.codehaus.mojo.sonar.SonarMojo#execute() caused a linkage error (java.lang.NoClassDefFoundError) and may be out-of-date. Check the realms:
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - [FATAL ERROR] Plugin realm = app0.child-container[org.codehaus.mojo:sonar-maven-plugin:1.0]
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[0] = file:/data/quickbuild/.m2/repository/org/codehaus/mojo/sonar-maven-plugin/1.0/sonar-maven-plugin-1.0.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[1] = file:/data/quickbuild/.m2/repository/org/codehaus/plexus/plexus-utils/1.4.1/plexus-utils-1.4.1.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - [FATAL ERROR] Container realm = plexus.core
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - urls[0] = file:/data/tools/apache-maven-2.2.1/lib/maven-2.2.1-uber.jar
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] ------------------------------------------------------------------------
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - [ERROR] FATAL ERROR
  13:55:44,139 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] ------------------------------------------------------------------------
  13:55:44,142 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] org/apache/commons/pool/KeyedObjectPoolFactory
  13:55:44,142 [master&gt;run Sonar@buildserver:8810] INFO  - org.apache.commons.pool.KeyedObjectPoolFactory
  13:55:44,142 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] ------------------------------------------------------------------------
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] Trace
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  - java.lang.NoClassDefFoundError: org/apache/commons/pool/KeyedObjectPoolFactory
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.apache.commons.dbcp.BasicDataSourceFactory.createDataSource(BasicDataSourceFactory.java:167)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.sonar.core.persistence.DefaultDatabase.initDatasource(DefaultDatabase.java:131)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.sonar.core.persistence.DefaultDatabase.start(DefaultDatabase.java:68)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at java.lang.reflect.Method.invoke(Method.java:597)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.picocontainer.lifecycle.ReflectionLifecycleStrategy.invokeMethod(ReflectionLifecycleStrategy.java:110)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.picocontainer.lifecycle.ReflectionLifecycleStrategy.start(ReflectionLifecycleStrategy.java:89)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.picocontainer.injectors.AbstractInjectionFactory$LifecycleAdapter.start(AbstractInjectionFactory.java:84)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.picocontainer.behaviors.AbstractBehavior.start(AbstractBehavior.java:169)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.picocontainer.behaviors.Stored$RealComponentLifecycle.start(Stored.java:132)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.picocontainer.behaviors.Stored.start(Stored.java:110)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.picocontainer.DefaultPicoContainer.potentiallyStartAdapter(DefaultPicoContainer.java:1015)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.picocontainer.DefaultPicoContainer.startAdapters(DefaultPicoContainer.java:1008)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.picocontainer.DefaultPicoContainer.start(DefaultPicoContainer.java:766)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.sonar.api.platform.ComponentContainer.startComponents(ComponentContainer.java:87)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.sonar.api.platform.ComponentContainer.execute(ComponentContainer.java:73)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.sonar.batch.bootstrapper.Batch.startBatch(Batch.java:86)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.sonar.batch.bootstrapper.Batch.execute(Batch.java:68)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.sonar.maven.SonarMojo.execute(SonarMojo.java:150)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPluginManager.java:490)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.codehaus.mojo.sonar.Bootstraper.executeMojo(Bootstraper.java:98)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.codehaus.mojo.sonar.Bootstraper.start(Bootstraper.java:79)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.codehaus.mojo.sonar.SonarMojo.execute(SonarMojo.java:88)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPluginManager.java:490)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:694)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeStandaloneGoal(DefaultLifecycleExecutor.java:569)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(DefaultLifecycleExecutor.java:539)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHandleFailures(DefaultLifecycleExecutor.java:387)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegments(DefaultLifecycleExecutor.java:284)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLifecycleExecutor.java:180)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:328)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:138)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.apache.maven.cli.MavenCli.main(MavenCli.java:362)
  13:55:44,143 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.apache.maven.cli.compat.CompatibleMain.main(CompatibleMain.java:60)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at java.lang.reflect.Method.invoke(Method.java:597)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.codehaus.classworlds.Launcher.launchEnhanced(Launcher.java:315)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.codehaus.classworlds.Launcher.launch(Launcher.java:255)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:430)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.codehaus.classworlds.Launcher.main(Launcher.java:375)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  - Caused by: java.lang.ClassNotFoundException: org.apache.commons.pool.KeyedObjectPoolFactory
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at java.security.AccessController.doPrivileged(Native Method)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.codehaus.classworlds.RealmClassLoader.loadClassDirect(RealmClassLoader.java:195)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.codehaus.classworlds.DefaultClassRealm.loadClass(DefaultClassRealm.java:255)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.codehaus.classworlds.DefaultClassRealm.loadClass(DefaultClassRealm.java:274)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at org.codehaus.classworlds.RealmClassLoader.loadClass(RealmClassLoader.java:214)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  -     ... 44 more
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] ------------------------------------------------------------------------
  13:55:44,144 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] Total time: 19 seconds
  13:55:44,147 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] Finished at: Fri Jul 12 13:55:44 EDT 2013
  13:55:44,430 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] Final Memory: 67M/494M
  13:55:44,430 [master&gt;run Sonar@buildserver:8810] INFO  - [INFO] ------------------------------------------------------------------------
  13:55:44,475 [master&gt;run Sonar@buildserver:8810] INFO  - Executing post-execute action...
  </code></pre>