I started at the top of these posting and worked my way through the advice. Things got better but eventually I had the exact same error no matter what I did.
ImportError: dynamic module does not define init function (init_mysql).
Towards the bottom of the list people are having the same headaches. I managed to fix it eventually with advice from this posting.
http://forum.webfaction.com/viewtopic.php?pid=5807#p5807
I am working on Mac OS 10.4.11 with Python 2.5 rather than 10.5 and this still worked fine. I also used the package format (x86) dmg from the MySQL 5.1 downloaded page as my install. I hope this also gets you up and running.
Please note that I didn't need to copy all files starting with libmysqlclient into the folder /usr/local/mysql/lib/mysql as I had done this already in working my way through some of the other suggestions.
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