title: loader constraint violation while running testcases in grails using maven
body: <p>I am running testcases in grails using maven and got the following stacktrace. </p>
  
  <p>I have the following conflicts.</p>
  
  <pre><code>loader constraint violation: when resolving field "DATETIME" the class loader (instance of org/codehaus/groovy/grails/cli/support/GrailsRootLoader) of the referring class, javax/xml/datatype/DatatypeConstants, and the class loader (instance of &lt;bootloader&gt;) for the field's resolved type, javax/xml/namespace/QName, have different Class objects for that type
  
  java.lang.LinkageError: loader constraint violation: when resolving field "DATETIME" the class loader (instance of org/codehaus/groovy/grails/cli/support/GrailsRootLoader) of the referring class, javax/xml/datatype/DatatypeConstants, and the class loader (instance of &lt;bootloader&gt;) for the field's resolved type, javax/xml/namespace/QName, have different Class objects for that type
      at com.sun.xml.bind.v2.model.impl.RuntimeBuiltinLeafInfoImpl.&lt;clinit&gt;(RuntimeBuiltinLeafInfoImpl.java:224)
      at com.sun.xml.bind.v2.model.impl.RuntimeTypeInfoSetImpl.&lt;init&gt;(RuntimeTypeInfoSetImpl.java:61)
      at com.sun.xml.bind.v2.model.impl.RuntimeModelBuilder.createTypeInfoSet(RuntimeModelBuilder.java:127)
      at com.sun.xml.bind.v2.model.impl.RuntimeModelBuilder.createTypeInfoSet(RuntimeModelBuilder.java:79)
      at com.sun.xml.bind.v2.model.impl.ModelBuilder.&lt;init&gt;(ModelBuilder.java:152)
      at com.sun.xml.bind.v2.model.impl.RuntimeModelBuilder.&lt;init&gt;(RuntimeModelBuilder.java:87)
      at com.sun.xml.bind.v2.runtime.JAXBContextImpl.getTypeInfoSet(JAXBContextImpl.java:422)
      at com.sun.xml.bind.v2.runtime.JAXBContextImpl.&lt;init&gt;(JAXBContextImpl.java:286)
      at com.sun.xml.bind.v2.ContextFactory.createContext(ContextFactory.java:139)
      at com.sun.xml.bind.v2.ContextFactory.createContext(ContextFactory.java:117)
      at javax.xml.bind.ContextFinder.newInstance(ContextFinder.java:211)
      at javax.xml.bind.ContextFinder.find(ContextFinder.java:372)
      at javax.xml.bind.JAXBContext.newInstance(JAXBContext.java:574)
      at javax.xml.bind.JAXBContext.newInstance(JAXBContext.java:522)
      at com.sun.xml.ws.spi.ProviderImpl$2.run(ProviderImpl.java:220)
      at com.sun.xml.ws.spi.ProviderImpl$2.run(ProviderImpl.java:218)
      at java.security.AccessController.doPrivileged(Native Method)
      at com.sun.xml.ws.spi.ProviderImpl.getEPRJaxbContext(ProviderImpl.java:217)
      at com.sun.xml.ws.spi.ProviderImpl.&lt;clinit&gt;(ProviderImpl.java:88)
      at java.lang.Class.newInstance0(Class.java:355)
      at java.lang.Class.newInstance(Class.java:308)
      at javax.xml.ws.spi.FactoryFinder.newInstance(FactoryFinder.java:36)
      at javax.xml.ws.spi.FactoryFinder.find(FactoryFinder.java:95)
      at javax.xml.ws.spi.Provider.provider(Provider.java:82)
      at javax.xml.ws.Service.&lt;init&gt;(Service.java:56)
      at javax.xml.ws.Service.create(Service.java:698)
      at com.j2.api.fax.myaccount.client.MyaccountClient$1.makeObject(MyaccountClient.java:28)
      at org.apache.commons.pool.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:1148)
      at com.j2.api.fax.myaccount.client.MyaccountClient.authenticateByPhoneNumber(MyaccountClient.java:66)
      at com.j2.api.fax.myaccount.client.MyaccountClient$authenticateByPhoneNumber.call(Unknown Source)
      at com.j2.helpers.LoginHelper.authenticateCustomerByPhoneNumber(LoginHelper.groovy:86)
      at com.j2.helpers.LoginHelper$authenticateCustomerByPhoneNumber.call(Unknown Source)
      at com.j2.spa.MobileService.login(MobileService.groovy:508)
      at com.j2.spa.MobileService$login.call(Unknown Source)
      at com.j2.spa.MobileController$_closure7.doCall(MobileController.groovy:109)
      at com.j2.spa.MobileController$_closure7.call(MobileController.groovy)
      at MobileControllerTests.testLogin_Failure_UsernameNotFound(MobileControllerTests.groovy:42)
  </code></pre>
  
  <p>I have tried a lot, but can't resolved it.</p>
  
  <p>Any Help is greatly appriciated..
  Thanks</p>