We have a very strange issue affecting two of our developers (the rest of the team with the same configuration do not have problems).  When they attempt to launch Arquillian tests from within Eclipse (via Run As > JUnit Test) they get the following exception:

java.lang.NoClassDefFoundError: org/jboss/threads/JBossThreadFactory
     at org.jboss.as.controller.client.impl.ClientConfigurationImpl.createDefaultExecutor(ClientConfigurationImpl.java:55)
     at org.jboss.as.controller.client.impl.ClientConfigurationImpl.create(ClientConfigurationImpl.java:146)
     at org.jboss.as.controller.client.ModelControllerClient$Factory.create(ModelControllerClient.java:201)
     at org.jboss.as.arquillian.container.CommonDeployableContainer.start(CommonDeployableContainer.java:88)
     at org.arquillian.container.chameleon.controller.TargetController$2.call(TargetController.java:86)
     at org.arquillian.container.chameleon.controller.TargetController$2.call(TargetController.java:83)
     at org.arquillian.container.chameleon.controller.TargetController.lifecycle(TargetController.java:161)
     at org.arquillian.container.chameleon.controller.TargetController.start(TargetController.java:83)
     at org.arquillian.container.chameleon.ChameleonContainer.start(ChameleonContainer.java:116)
     at org.jboss.arquillian.container.impl.ContainerImpl.start(ContainerImpl.java:179)
     at org.jboss.arquillian.container.impl.client.container.ContainerLifecycleController$8.perform(ContainerLifecycleController.java:137)
     at org.jboss.arquillian.container.impl.client.container.ContainerLifecycleController$8.perform(ContainerLifecycleController.java:133)
     at org.jboss.arquillian.container.impl.client.container.ContainerLifecycleController.forContainer(ContainerLifecycleController.java:208)
     at org.jboss.arquillian.container.impl.client.container.ContainerLifecycleController.startContainer(ContainerLifecycleController.java:133)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
     at java.lang.reflect.Method.invoke(Method.java:498)
     at org.jboss.arquillian.core.impl.ObserverImpl.invoke(ObserverImpl.java:86)
     at org.jboss.arquillian.core.impl.EventContextImpl.invokeObservers(EventContextImpl.java:103)
     at org.jboss.arquillian.core.impl.EventContextImpl.proceed(EventContextImpl.java:90)
     at org.jboss.arquillian.container.impl.client.ContainerDeploymentContextHandler.createContainerContext(ContainerDeploymentContextHandler.java:54)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
     at java.lang.reflect.Method.invoke(Method.java:498)
     at org.jboss.arquillian.core.impl.ObserverImpl.invoke(ObserverImpl.java:86)
     at org.jboss.arquillian.core.impl.EventContextImpl.proceed(EventContextImpl.java:95)
     at org.jboss.arquillian.core.impl.ManagerImpl.fire(ManagerImpl.java:133)
     at org.jboss.arquillian.core.impl.ManagerImpl.fire(ManagerImpl.java:105)
     at org.jboss.arquillian.core.impl.EventImpl.fire(EventImpl.java:62)
     at org.jboss.arquillian.container.impl.client.container.ContainerLifecycleController$2.perform(ContainerLifecycleController.java:70)
     at org.jboss.arquillian.container.impl.client.container.ContainerLifecycleController$2.perform(ContainerLifecycleController.java:64)
     at org.jboss.arquillian.container.impl.client.container.ContainerLifecycleController.forEachSuiteContainer(ContainerLifecycleController.java:181)
     at org.jboss.arquillian.container.impl.client.container.ContainerLifecycleController.startSuiteContainers(ContainerLifecycleController.java:64)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
     at java.lang.reflect.Method.invoke(Method.java:498)
     at org.jboss.arquillian.core.impl.ObserverImpl.invoke(ObserverImpl.java:86)
     at org.jboss.arquillian.core.impl.EventContextImpl.invokeObservers(EventContextImpl.java:103)
     at org.jboss.arquillian.core.impl.EventContextImpl.proceed(EventContextImpl.java:90)
     at org.jboss.arquillian.core.impl.ManagerImpl.fire(ManagerImpl.java:133)
     at org.jboss.arquillian.core.impl.ManagerImpl.fire(ManagerImpl.java:105)
     at org.jboss.arquillian.core.impl.EventImpl.fire(EventImpl.java:62)
     at org.jboss.arquillian.container.test.impl.client.ContainerEventController.execute(ContainerEventController.java:83)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
     at java.lang.reflect.Method.invoke(Method.java:498)
     at org.jboss.arquillian.core.impl.ObserverImpl.invoke(ObserverImpl.java:86)
     at org.jboss.arquillian.core.impl.EventContextImpl.invokeObservers(EventContextImpl.java:103)
     at org.jboss.arquillian.core.impl.EventContextImpl.proceed(EventContextImpl.java:90)
     at org.jboss.arquillian.test.impl.TestContextHandler.createSuiteContext(TestContextHandler.java:69)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
     at java.lang.reflect.Method.invoke(Method.java:498)
     at org.jboss.arquillian.core.impl.ObserverImpl.invoke(ObserverImpl.java:86)
     at org.jboss.arquillian.core.impl.EventContextImpl.proceed(EventContextImpl.java:95)
     at org.jboss.arquillian.core.impl.ManagerImpl.fire(ManagerImpl.java:133)
     at org.jboss.arquillian.core.impl.ManagerImpl.fire(ManagerImpl.java:105)
     at org.jboss.arquillian.test.impl.EventTestRunnerAdaptor.beforeSuite(EventTestRunnerAdaptor.java:71)
     at org.jboss.arquillian.junit.AdaptorManager.initializeAdaptor(AdaptorManager.java:23)
     at org.jboss.arquillian.junit.AdaptorManagerWithNotifier.initializeAdaptor(AdaptorManagerWithNotifier.java:19)
     at org.jboss.arquillian.junit.Arquillian.run(Arquillian.java:109)
     at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
     at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:538)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:760)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:460)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:206)
Caused by: java.lang.ClassNotFoundException: org.jboss.threads.JBossThreadFactory
     at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
     at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
     ... 72 more

The same tests run fine for these two developers via maven clean verify.  We are using arquillian-bom 1.4.0.Final in conjunction with arquillian-container-chameleon 1.0.0.CR2.  We've confirmed that ~/.m2/repository/org/jboss/threads/jboss-threads/2.0.0.GA/jboss-threads-2.0.0.GA.jar is not corrupt (though presumably a launch via Maven would also fail for these developers if this were the case.)

Our arquillian.xml:

  xsi:schemaLocation="http://jboss.org/schema/arquillian http://jboss.org/schema/arquillian/arquillian_1_0.xsd">

  
    
    target/arquillian-deployments
  

  
    
      jboss eap:6.4:remote
      localhost
      
      10019
    
  

As mentioned above, this configuration works for all the other members of the team but does not for two of them.  The only difference we've been able to find is that the usernames for these two developers exceeds 8 characters but we can't see how that would be the cause...

Any ideas on how to resolve this or get more information?

Thanks!