I was about to post the same, here is my bt:
(gdb) run
Starting program: /usr/local/bin/amuled
warning: Unable to find dynamic linker breakpoint function.
GDB will be unable to debug shared library initializers
and track explicitly loaded dynamic code.
[Thread debugging using libthread_db enabled]
[New Thread -1213325200 (LWP 28229)]
Initialising aMule
Detaching after fork from child process 28232.
Checking if there is an instance already running...
[New Thread -1215693904 (LWP 28233)]
Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread -1215693904 (LWP 28233)]
0xb7f7ba6c in wxMutex::Lock() () from /usr/local/lib/libwx_base-2.5.so.5
(gdb) bt
#0 0xb7f7ba6c in wxMutex::Lock() () from /usr/local/lib/libwx_base-2.5.so.5
#1 0xb7fb06f4 in ?? () from /usr/local/lib/libwx_base-2.5.so.5
#2 0xb789f898 in ?? ()
#3 0xb7f7d985 in wxEvtHandler::AddPendingEvent(wxEvent&) () from /usr/local/lib/libwx_base-2.5.so.5
Previous frame inner to this frame (corrupt stack?)
(gdb) bt full
#0 0xb7f7ba6c in wxMutex::Lock() () from /usr/local/lib/libwx_base-2.5.so.5
No symbol table info available.
#1 0xb7fb06f4 in ?? () from /usr/local/lib/libwx_base-2.5.so.5
No symbol table info available.
#2 0xb789f898 in ?? ()
No symbol table info available.
#3 0xb7f7d985 in wxEvtHandler::AddPendingEvent(wxEvent&) () from /usr/local/lib/libwx_base-2.5.so.5
No symbol table info available.
Regards--