title: Maven build corrupting jar files in /WEB-INF/lib folder
body: <p>Everytime I build my maven project and run the application, it says</p>
  
  <pre><code>[INFO] 
  [INFO] Jan 07, 2015 5:23:37 PM com.google.apphosting.utils.jetty.JettyLogger warn
  [INFO] WARNING: Failed to read file: C:\app\target\app-1.0\WEB-INF\lib\datanucleus-jpa-1.1.5.jar
  [INFO] java.util.zip.ZipException: error in opening zip file
  [INFO]  at java.util.zip.ZipFile.open(Native Method)
  [INFO]  at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:215)
  [INFO]  at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:145)
  [INFO]  at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:153)
  [INFO]  at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:117)
  [INFO]  at org.mortbay.jetty.webapp.TagLibConfiguration.configureWebApp(TagLibConfiguration.java:174)
  [INFO]  at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1247)
  [INFO]  at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:517)
  [INFO]  at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:467)
  [INFO]  at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
  [INFO]  at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
  [INFO]  at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
  [INFO]  at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
  [INFO]  at org.mortbay.jetty.Server.doStart(Server.java:224)
  [INFO]  at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
  [INFO]  at com.google.appengine.tools.development.JettyContainerService.startContainer(JettyContainerService.java:255)
  [INFO]  at com.google.appengine.tools.development.AbstractContainerService.startup(AbstractContainerService.java:288)
  [INFO]  at com.google.appengine.tools.development.AutomaticInstanceHolder.startUp(AutomaticInstanceHolder.java:26)
  [INFO]  at com.google.appengine.tools.development.AbstractModule.startup(AbstractModule.java:87)
  [INFO]  at com.google.appengine.tools.development.Modules.startup(Modules.java:105)
  [INFO]  at com.google.appengine.tools.development.DevAppServerImpl.doStart(DevAppServerImpl.java:258)
  [INFO]  at com.google.appengine.tools.development.DevAppServerImpl.access$000(DevAppServerImpl.java:47)
  [INFO]  at com.google.appengine.tools.development.DevAppServerImpl$1.run(DevAppServerImpl.java:213)
  [INFO]  at com.google.appengine.tools.development.DevAppServerImpl$1.run(DevAppServerImpl.java:211)
  [INFO]  at java.security.AccessController.doPrivileged(Native Method)
  [INFO]  at com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerImpl.java:211)
  [INFO]  at com.google.appengine.tools.development.DevAppServerMain$StartAction.apply(DevAppServerMain.java:277)
  [INFO]  at com.google.appengine.tools.util.Parser$ParseResult.applyArgs(Parser.java:48)
  [INFO]  at com.google.appengine.tools.development.DevAppServerMain.run(DevAppServerMain.java:219)
  [INFO]  at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMain.java:210)
  </code></pre>
  
  <p>for all the jars that I have added under /WEB-INF/lib</p>
  
  <p>This seems not to be happenning with other jars added in war through maven dependency.</p>
  
  <p>Here is my pom.xml</p>
  
  <pre><code>&lt;build&gt;
      &lt;outputDirectory&gt;target/${project.artifactId}-${project.version}/WEB-INF/classes&lt;/outputDirectory&gt;
      &lt;plugins&gt;
          &lt;plugin&gt;
              &lt;groupId&gt;org.apache.maven.plugins&lt;/groupId&gt;
              &lt;version&gt;3.1&lt;/version&gt;
              &lt;artifactId&gt;maven-compiler-plugin&lt;/artifactId&gt;
              &lt;configuration&gt;
                  &lt;source&gt;1.7&lt;/source&gt;
                  &lt;target&gt;1.7&lt;/target&gt;
              &lt;/configuration&gt;
          &lt;/plugin&gt;
          &lt;plugin&gt;
              &lt;groupId&gt;org.apache.maven.plugins&lt;/groupId&gt;
              &lt;artifactId&gt;maven-war-plugin&lt;/artifactId&gt;
              &lt;version&gt;2.4&lt;/version&gt;
              &lt;configuration&gt;
                  &lt;archiveClasses&gt;true&lt;/archiveClasses&gt;
                  &lt;webResources&gt;
                      &lt;resource&gt;
                          &lt;directory&gt;${basedir}/src/main/webapp/WEB-INF&lt;/directory&gt;
                          &lt;filtering&gt;true&lt;/filtering&gt;
                          &lt;targetPath&gt;WEB-INF&lt;/targetPath&gt;
                      &lt;/resource&gt;
                  &lt;/webResources&gt;
              &lt;/configuration&gt;
          &lt;/plugin&gt;
          &lt;plugin&gt;
              &lt;groupId&gt;com.google.appengine&lt;/groupId&gt;
              &lt;artifactId&gt;appengine-maven-plugin&lt;/artifactId&gt;
              &lt;version&gt;${appengine.target.version}&lt;/version&gt;
              &lt;configuration&gt;
                  &lt;enableJarClasses&gt;false&lt;/enableJarClasses&gt;
                  &lt;address&gt;0.0.0.0&lt;/address&gt;
                  &lt;jvmFlags&gt;
                      &lt;jvmFlag&gt;-Xdebug&lt;/jvmFlag&gt;
                      &lt;jvmFlag&gt;-agentlib:jdwp=transport=dt_socket,address=8000,server=y,suspend=n&lt;/jvmFlag&gt;
                      &lt;jvmFlag&gt;-Ddatastore.backing_store=${project.basedir}\local_db.bin&lt;/jvmFlag&gt;
                  &lt;/jvmFlags&gt;
              &lt;/configuration&gt;
          &lt;/plugin&gt;
      &lt;/plugins&gt;
  &lt;/build&gt;
  </code></pre>
  
  <p>Downloading the jars again does not help me. I did it several times. Pleas help me to fix this.</p>