FULL PRODUCT VERSION :
java version "1.6.0_18"
Java(TM) SE Runtime Environment (build 1.6.0_18-b07)
Java HotSpot(TM) Server VM (build 16.0-b13, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Linux lxubuntu03 2.6.31-17-generic #54-Ubuntu SMP Thu Dec 10 16:20:31 UTC 2009 i686 GNU/Linux

A DESCRIPTION OF THE PROBLEM :
We are seeing problems in CORBA calls starting with JDK6 Update 18 (Update 17 works o.k.), see the error message below

We are using a proprietary CORBA load balancing system based on GIOP LOCATION_FORWARD messages, CORBA calls bypassing this load balancing mechanism still work o.k.


ERROR MESSAGES/STACK TRACES THAT OCCUR :
Feb 18, 2010 2:04:18 PM com.sun.corba.se.impl.orb.ORBImpl finishedDispatch
WARNING: "IOP00710261: (INTERNAL) Number of invocations is already zero, but another invocation has completed"
org.omg.CORBA.INTERNAL: vmcid: SUN minor code: 261 completed: Yes
at com.sun.corba.se.impl.logging.ORBUtilSystemException.numInvocationsAlreadyZero(ORBUtilSystemException.java:5248)
at com.sun.corba.se.impl.logging.ORBUtilSystemException.numInvocationsAlreadyZero(ORBUtilSystemException.java:5262)
at com.sun.corba.se.impl.orb.ORBImpl.finishedDispatch(ORBImpl.java:1341)
at com.sun.corba.se.impl.orb.ORBImpl.releaseOrDecrementInvocationInfo(ORBImpl.java:1806)
at com.sun.corba.se.impl.protocol.CorbaClientDelegateImpl.releaseReply(CorbaClientDelegateImpl.java:138)
at org.omg.CORBA.portable.ObjectImpl._releaseReply(ObjectImpl.java:474)


REPRODUCIBILITY :
This bug can be reproduced always.

Release Regression From : 6u17
The above release value was the last known release where this
bug was not reproducible. Since then there has been a regression.

Release Regression From : 6u17
The above release value was the last known release where this
bug was not reproducible. Since then there has been a regression.