The following NSK tests fail when run with the -XX:+UseConcMarkSweepGC +ExplicitGCInvokesConcurrent options:

        nsk/jvmti/scenarios/allocation/AP03/ap03t001
        nsk/jvmti/scenarios/capability/CM02/cm02t001
        nsk/jvmti/unit/heap/BasicTagTests

The link to the failure logs is here:
 http://vmsqe.sfbay/nightly/mantis/DTWS/results/08-07-06/ClientVM/solx86/mixed/Gc_Baseline-Xconc/nsk.jvmti-08-NIGHTLY-Gc_Baseline-Xconc-ClientVM-mixed-solx86-2006-08-08-00-32-12/analysis.html#New_Failures

and a sample tlog is:

#!/usr/bin/sh

CLASSPATH=/net/gtee.sfbay/export/nightly/mustang/DTWS/results/08-07-06/ClientVM/solx86/mixed/Gc_Baseline-Xconc/WORK_DIR/nsk.jvmti-08-NIGHTLY-Gc_Baseline-Xconc-ClientVM-mixed-solx86-2006-08-08-00-32-12/run2/gridadm.Solaris.x86/BasicTagTests:/net/gtee.sfbay/export/gtee/suites/testbase_vm.1.6/vm/bin/classes:/net/gtee.sfbay/export/nightly/mustang/JDK/gc_baseline/jdk1.6/solaris-i586/lib/tools.jar
HOME=/var/tmp
RAS_OPTIONS=
LD_LIBRARY_PATH=/net/gtee.sfbay/export/gtee/suites/testbase_vm.1.6/vm/bin/lib/solaris-i586/nsk/share/jvmti/unit:/net/gtee.sfbay/export/gtee/suites/testbase_vm.1.6/vm/src/nsk/share/lib/solaris-i586:/net/gtee.sfbay/export/nightly/mustang/JDK/gc_baseline/jdk1.6/solaris-i586/jre/lib/i386/client
PATH=/net/gtee.sfbay/export/nightly/mustang/JDK/gc_baseline/jdk1.6/solaris-i586/bin:/net/gtee.sfbay/export/nightly/mustang/JDK/gc_baseline/jdk1.6/solaris-i586/jre/bin:/bin:/usr/bin:/net/gtee.sfbay/export/nightly/mustang/JDK/gc_baseline/jdk1.6/solaris-i586/jre/bin:/mksnt
DISPLAY=vmsqe.sfbay:0.0
SHELL=/usr/bin/sh

while [ $# -gt 0 ];
do
  if [ $1 = "-jdk" ]; then
shift 1
PATH=${1}/bin:${PATH}
shift 1
  else
if [ $1 = "-d" ]; then
shift 1
if [ $# -gt 0 ]; then
DISPLAY=$1
shift 1
else
DISPLAY=:0.0
fi
fi
  fi
done

export CLASSPATH
export HOME
export RAS_OPTIONS
export LD_LIBRARY_PATH
export PATH
export DISPLAY
export SHELL

#annotate TEST javaopt=-client -Xmixed -XX:-PrintVMOptions -XX:+UseConcMarkSweepGC -XX:+CMSPermGenSweepingEnabled -XX:+CMSClassUnloadingEnabled -XX:+ExplicitGCInvokesConcurrent -agentlib:Heap=-waittime=2
/net/gtee.sfbay/export/nightly/mustang/JDK/gc_baseline/jdk1.6/solaris-i586/bin/java -client -Xmixed -DHANGINGJAVA19459 -XX:-PrintVMOptions -XX:+UseConcMarkSweepGC -XX:+CMSPermGenSweepingEnabled -XX:+CMSClassUnloadingEnabled -XX:+ExplicitGCInvokesConcurrent -agentlib:Heap=-waittime=2 nsk.jvmti.unit.heap.BasicTagTests
##Exit status of execution step=1
##!checkExitCode

#VM option '-PrintVMOptions'
#VM option '+UseConcMarkSweepGC'
#VM option '+CMSPermGenSweepingEnabled'
#VM option '+CMSClassUnloadingEnabled'
#VM option '+ExplicitGCInvokesConcurrent'

#Exception in thread "main" java.lang.RuntimeException: Test failed - object not tagged
# at nsk.jvmti.unit.heap.BasicTagTests.run(BasicTagTests.java:51)
# at nsk.jvmti.unit.heap.BasicTagTests.main(BasicTagTests.java:23)
Also failing

nsk/jvmti/scenarios/allocation/AP01/ap01t001
nsk/hprof/regression/HeapThrasher (with G1)