Uh-oh.
That's the kind of crash which is hard-going-on-impossible to track down.

What happened is that the memory heap structure got damaged (probably by accessing an already deleted object) and then, some time later, aMule blows up on a perfectly innocent memory allocation. So the backtrace doesn't give a clue to the nature of the problem.
Are you always running aMule from gdb, or have you found a way to somehow reproduce the problem?