Swingmark test crashes at genCollectedHeap.cpp in Xcomp

Swingmark test crashes at genCollectedHeap.cpp in Xcomp mode
This assertion was seen from b09 of promoted build. Happens easily on Solx86.
Fails in all the three modes Int, mixed and Comp with two repeat and 2 threads.

To reproduce :

 Go to /net/jano.sfbay/export/disk20/GammaBase/Bugs/{BugId}
 execute the rerun.sh


Assertion is :

#
# HotSpot Virtual Machine Error, assertion failure
# Please report this error at
# http://java.sun.com/cgi-bin/bugreport.cgi
#
# Java VM: Java HotSpot(TM) Server VM (1.4.1-beta-b10-debug compiled mode)
#
# assert(_gc_cause == GCCause::_no_gc, "Cause of GC should not be set yet")
#
# Error ID: /BUILD_AREA/jdk1.4.1/hotspot/src/share/vm/memory/genCollectedHeap.cpp, 459
#
# Problematic Thread: prio=5 tid=0x823fee0 nid=0xd runnable
#
Dumping core....