======= Backtrace: =========
/lib/libc.so.60xa10e31
perl(Perl_safesysfree+0x21)0x80cde41

I may guess that the problem is located in JVM termination. May be just keep $java reference somewhere?

While this does not solves the problem, I may suppose, that some wrong pattern is been used: launching everytime new JVM instance, could lead to huge overheads.