On Wed, 2006-06-28 at 17:27 +0100, Robert Lougher wrote: > Any chance you could provide some details? Yeah, sorry. Ok, here we go: This is jamvm-1.4.3 on x86_64-linux. Program received signal SIGSEGV, Segmentation fault. [Switching to Thread 1241594208 (LWP 25793)] objectLock (obj=0x2ade337c0008) at lock.c:314 314 if((entering = ATOMIC_READ(&mon->entering)) == UN_USED) (gdb) bt #0 objectLock (obj=0x2ade337c0008) at lock.c:314 #1 0x0000000000419f5e in threadStart (arg=<value optimized out>) at thread.c:315 #2 0x00002ade33399b1c in start_thread () from /lib/libpthread.so.0 #3 0x00002ade335759c2 in clone () from /lib/libc.so.6 #4 0x0000000000000000 in ?? () TWISTI