FYI, I also got this bug and I posted a new backtrace (see backtraces subforum for my backtrace with some debug info)
However I cannot reproduce it reliably.
By the way, I think blaming Ubuntu for this bug is wrong, people using Fedora 10 also got it. I inspected the wx patches they ship and they couldn't cause this bug. I'm not so sure about the GTK+ patches they ship, I'm investigating this point.
It could be a GTK+, WX or aMule bug, but I'm almost 100% sure this bug is not Ubuntu specific.