After many frustrating failures at installing DBD::mysql on my mac OS 10.3, I just performed the third of the 3 mentioned steps (that is, installing "msql-mysql-modules-1.2219") and bingo! First time! ++ to zetetes! Thank you!

Update: Just found this piece by Googling:

Should you need to install DBD::mysql on Panther, here's a few tips yo
+u might find helpful. First: DBD::mysql installation will likely fail
+ if you try to do it using the CPAN installer because it won't be con
+figured with your database settings. You'll need to manually install 
+it. Get it from CPAN here: DBD-mysql-2.9003 .

To create the Makefile you'll need to pass it your database's username
+ and password:
perl Makefile.PL --testuser=usename --testpassword=password
Next you'll need to add the following step (thanks to Casey West):
perl -pi -e's/MACOSX/env MACOSX/' Makefile


I also had to sudo make install which makes the whole process like so:
perl Makefile.PL --testuser=username --testpassword=password
perl -pi -e's/MACOSX/env MACOSX/' Makefile
make
make test
sudo make install
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