A month or two back used mysqldump incorrectly and found it caused a segfault.
Looks like the next version of MySQL is patched to fix it. The bug was not anything critical. I just point it out to illustrate how awesome it is work with open-source software vendors. You can watch the entire testing / patching process on a mailing list and know how close they are to resolving your problem. This is just another one of the many reasons I love open-source software.