java.lang.AssertionError: Same server added twice?

I was trying to create a Uniformely Distributed Topic, and at the moment I activate the changes I get:

the entire stacktrace is:

Caused by: java.lang.AssertionError: Same server added twice?

at weblogic.jms.backend.udd.SyntheticDDBean.addMember(SyntheticDDBean.java:68)
at weblogic.jms.backend.udd.UDDEntity.addMember(UDDEntity.java:203)
at weblogic.jms.backend.udd.UDDEntity.reconcileAddedMembers(UDDEntity.java:1050)
at weblogic.jms.backend.udd.UDDEntity.reconcileTargets(UDDEntity.java:1111)
at weblogic.jms.backend.udd.UDDEntity.broadcastChangeToAllUDDs(UDDEntity.java:928)
at weblogic.jms.backend.udd.UDDEntity.activateLocalJMSServer(UDDEntity.java:963)
at weblogic.jms.deployer.BEAdminHandler.activate(BEAdminHandler.java:226)
at weblogic.management.utils.GenericManagedService.activateDeployment(GenericManagedService.java:239)
at weblogic.management.utils.GenericServiceManager.activateDeployment(GenericServiceManager.java:131)
at weblogic.management.internal.DeploymentHandlerHome.invokeHandlers(DeploymentHandlerHome.java:632)
at weblogic.management.internal.DeploymentHandlerHome.access$400(DeploymentHandlerHome.java:67)
at weblogic.management.internal.DeploymentHandlerHome$1.activateUpdate(DeploymentHandlerHome.java:187)
at weblogic.descriptor.internal.DescriptorImpl$Update.activate(DescriptorImpl.java:491)
at weblogic.descriptor.internal.DescriptorImpl.activateUpdate(DescriptorImpl.java:230)
at weblogic.management.provider.internal.RuntimeAccessDeploymentReceiverService$1.run(RuntimeAccessDeploymentReceiverService.java:362)
at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)
at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:120)
at weblogic.management.provider.internal.RuntimeAccessDeploymentReceiverService.commit(RuntimeAccessDeploymentReceiverService.java:357)



What is a UDDEntity? And a UDD? Is it a Uniformely Distributed Destination?
And a SyntheticDDBean?


Anyway, I remove the "use default targeting" and explicitly use a Subdeployment, and I get this error message:

activateUpdate() called without first calling prepareUpdate()

Yet despite the errors everything seems to be activated correctly... weird...