Hallo
I figured out that I had to change the stack size...
Our config runs with -Xss=128k which is too small obviously, so I set it to 256k - that works.
During my research I encounterd this bug
http://bugs.sun.com/view_bug.do?bug_id=6434149
whichs says if you have a segmentation fault you should put
JAVA_OPTS="$JAVA_OPTS -Dsun.lang.ClassLoader.allowArraySyntax=true"
So that is Plan B if the first solution is not working.
Thanks for your help!