Hey,
Just an update...
I wasn't able to get amule to run properly within valgrind on my machine, it was to slow to load the servers and establsh a connection, seemed like it was timing out. So I gave up on it.
I noticed the following though, the crashes seem to only occur after I preview a video in mplayer, but not directly after.
After previewing the video if I try to do a search it sometimes crashes or if a file is near completion, as a few times when I restart amule after a crash a file will complete.
I updated aMule to 20070516 and still have the same problem.