Running two copies of a test client beating up on a few web-service methods produces "Ambiguous javaMethod: <method>" from org.jboss.ws.metadata.OperationMetaData(getJavaMethod) (line 203). There is no potential ambiguity since all methods have quite distinctive signatures and the problem is sporadic.
I believe this a lack of synchronization between multiple threads simultaneously trying to resolve the javaMethod field. Both see that javaMethod has not yet been set and the second to finish finds the javaMethod field has already been set by the first and mis-interprets this as an ambiguous method situation. Running a dual core processor exacerbates the problem.
Cannot use jboss with this bug.