Indeed, it does seem I was wrong. Sorry about that.
You should remove that line from your .gdbinit. The reason I thought it was a benign (or at least, expected) signal was the presence of "semaphore_wait_signal_trap" in the backtrace, which I assumed meant the program was specifically waiting for a SIGTRAP before it would proceed.
At this point, I'm at a bit of a loss as to how to proceed. To recap: the main problem we've identified is that amuled is opening enough file descriptors so that eventually you get a socket file descriptor higher than 1024, which is the limit for some data structures and system calls to handle properly. You don't seem to have excessive numbers of files open, and your Max. Connections is within reason, so the combined total should remain under 1024. So, we don't know why amuled seems to be exceeding that. We suspect that amuled is failing to close some of the connections it has opened, but neither netstat nor lsof have so far corroborated that suspicion. We would expect each of those to produce output with about 1000 lines if amuled was opening many, many connections and failing to close them.
In the meantime, peripheral to the main problem:
It is unclear why setting breakpoints doesn't seem to work for you.
Also, the patch I provided to prevent file descriptors from exceeding 1024 seems to have had weird, unexpected effects. In particular, you are seeing SIGTRAP signals that you weren't seeing before. We don't know whether or not the patch addresses the original problem.
We also don't know why you seem to be the only person having this problem. Perhaps few Mac users are using amuled. Perhaps they tried, got this error, but didn't report it.
More generally, we don't know why amuled has this problem while aMule.app doesn't. We don't know why amuled keeps about 100 more connections open at a time than aMule.app (according to netstat). Both of these are probably related to the fact that amuled seems to download faster than aMule.app.
Lastly, you have installed aMule under Ubuntu on your PowerBook and amuled works much better there. It neither has this crashing problem nor does it exhibit the slow downloads that are apparently endemic to Mac aMule. Since this remains a big-endian platform, we can eliminate endianness issues as the cause of either of those two problems.
