Here is the backtrace... Not sure it'll help. I'm bzipping the coredump, and see if it's not too big...
(no debugging symbols found)
Using host libthread_db library "/lib/i686/cmov/libthread_db.so.1".
Core was generated by `./penumbra.bin'.
Program terminated with signal 6, Aborted.
#0 0xffffe410 in __kernel_vsyscall ()
(gdb) thread apply all bt full
Thread 4 (process 8152):
#0 0xffffe410 in __kernel_vsyscall ()
No symbol table info available.
#1 0xb7771b46 in ?? ()
No symbol table info available.
Thread 3 (process 8153):
#0 0xffffe410 in __kernel_vsyscall ()
No symbol table info available.
#1 0xb77ab321 in ?? ()
No symbol table info available.
Thread 2 (process 8154):
#0 0xffffe410 in __kernel_vsyscall ()
No symbol table info available.
#1 0xb7771b46 in ?? ()
No symbol table info available.
Thread 1 (process 8151):
#0 0xffffe410 in __kernel_vsyscall ()
No symbol table info available.
#1 0xb7706f15 in ?? ()
No symbol table info available.
PS: 50Mo bzipped... I won't upload it.