Just me? Debugged JVM's hanging, preventing IPL?

Hi.

I have had a problem for quite some time when debugging Java programs on V5R3M0 from Eclipse on PC, namely that once in a while the JVM gives a strange message and then hangs. It does not take any notice of me trying to end the job, either with SysReq-2 *I or with the 4 option in wrkactjob. It just sits there (the one I have now is in THDW).

Our system administrator reports that these jobs prevent the weekly IPL for backups, which annoys him (which everyone is something you should not take lightly), and that we should be fully up to date on fixpaks and PTF's.

The Java program is invoked with JAVA from CL as an executable jar (no sealings, just a class-path in the manifest) with the following SystemDefault.properties in effect, and no special options in the JAVA invocation:

========
java.version=1.4
java.compiler=jitc

# Easy way to see if this file is read... same as -verbose
#os400.run.verbose=true
#
os400.xrun.option=jdwp:transport=dt_socket,address=7999,server=y,suspend=y
========

This means that it fires up the JVM and wait for me to attach with the debugger before starting the program. It then runs and once in a while, in an inreproducible way to me, complains and hang.

Has anybody but me seen a similar behaviour?