TeamCity 5 in Jboss 6 fails to start

I'm trying to get TeamCity 5 running on our Jboss 6 instance. I've followed the (simple) instructions for installing in a Java EE Container, which basically consists of dropping the WAR file into the deploy (webapp) directory.

When I try to start the WAR, I get the attached exception. Any experience or advice running TeamCity in Jboss would be welcome.

java.lang.RuntimeException: org.jboss.deployers.client.spi.IncompleteDeploymentException: Summary of incomplete deployments (SEE PREVIOUS ERRORS FOR DETAILS):

*** DEPLOYMENTS IN ERROR: Name -> Error

vfszip:/usr/local/jboss-6.0.0.20100216-M2/server/default/deploy/teamCity.war/ -> org.jboss.deployers.spi.DeploymentException: Error during deploy: vfszip:/usr/local/jboss-6.0.0.20100216-M2/server/default/deploy/teamCity.war/

DEPLOYMENTS IN ERROR:

  Deployment "vfszip:/usr/local/jboss-6.0.0.20100216-M2/server/default/deploy/teamCity.war/" is in error due to the following reason(s): java.lang.LinkageError: loader constraint violation: when resolving overridden method "jetbrains.buildServer.util.FileUtil$1.resolveEntity(Ljava/lang/String;Ljava/lang/String;)Lorg/xml/sax/InputSource;" the class loader (instance of org/jboss/classloader/spi/base/BaseClassLoader) of the current class, jetbrains/buildServer/util/FileUtil$1, and its superclass loader (instance of <bootloader>), have different Class objects for the type org/xml/sax/InputSource used in the signature

        at org.jboss.profileservice.management.client.upload.StreamingDeploymentTarget.invoke(StreamingDeploymentTarget.java:312)

        at org.jboss.profileservice.management.client.upload.StreamingDeploymentTarget.start(StreamingDeploymentTarget.java:189)

        at org.jboss.profileservice.management.client.upload.DeploymentProgressImpl.start(DeploymentProgressImpl.java:232)

        at org.jboss.profileservice.management.client.upload.DeploymentProgressImpl.run(DeploymentProgressImpl.java:89)

        at org.rhq.plugins.jbossas5.util.DeploymentUtils.run(DeploymentUtils.java:155)

        at org.rhq.plugins.jbossas5.AbstractManagedDeploymentComponent.invokeOperation(AbstractManagedDeploymentComponent.java:173)

        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)

        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)

        at java.lang.reflect.Method.invoke(Method.java:597)

        at org.rhq.core.pc.inventory.ResourceContainer$ComponentInvocationThread.call(ResourceContainer.java:525)

        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)

        at java.util.concurrent.FutureTask.run(FutureTask.java:138)

        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:885)

        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)

        at java.lang.Thread.run(Thread.java:619)

Caused by: org.jboss.deployers.client.spi.IncompleteDeploymentException: Summary of incomplete deployments (SEE PREVIOUS ERRORS FOR DETAILS):

*** DEPLOYMENTS IN ERROR: Name -> Error

vfszip:/usr/local/jboss-6.0.0.20100216-M2/server/default/deploy/teamCity.war/ -> org.jboss.deployers.spi.DeploymentException: Error during deploy: vfszip:/usr/local/jboss-6.0.0.20100216-M2/server/default/deploy/teamCity.war/

DEPLOYMENTS IN ERROR:

  Deployment "vfszip:/usr/local/jboss-6.0.0.20100216-M2/server/default/deploy/teamCity.war/" is in error due to the following reason(s): java.lang.LinkageError: loader constraint violation: when resolving overridden method "jetbrains.buildServer.util.FileUtil$1.resolveEntity(Ljava/lang/String;Ljava/lang/String;)Lorg/xml/sax/InputSource;" the class loader (instance of org/jboss/classloader/spi/base/BaseClassLoader) of the current class, jetbrains/buildServer/util/FileUtil$1, and its superclass loader (instance of <bootloader>), have different Class objects for the type org/xml/sax/InputSource used in the signature

        at org.jboss.deployers.plugins.deployers.DeployersImpl.checkComplete(DeployersImpl.java:1198)

        at org.jboss.deployers.plugins.deployers.DeployersImpl.checkComplete(DeployersImpl.java:1144)

        at org.jboss.deployers.plugins.main.MainDeployerImpl.checkComplete(MainDeployerImpl.java:848)

        at org.jboss.system.server.profileservice.repository.MainDeployerAdapter.checkComplete(MainDeployerAdapter.java:128)

        at org.jboss.profileservice.management.upload.remoting.AbstractDeployHandler.start(AbstractDeployHandler.java:326)

        at org.jboss.profileservice.management.upload.remoting.AbstractDeployHandler.invoke(AbstractDeployHandler.java:238)

        at org.jboss.remoting.ServerInvoker.invoke(ServerInvoker.java:897)

        at org.jboss.remoting.transport.local.LocalClientInvoker.invoke(LocalClientInvoker.java:106)

        at org.jboss.remoting.Client.invoke(Client.java:1927)

        at org.jboss.remoting.Client.invoke(Client.java:770)

        at org.jboss.profileservice.management.client.upload.StreamingDeploymentTarget.invoke(StreamingDeploymentTarget.java:304)

        ... 15 more