Just wondering, since you mention PHP as an alternative -- have you ever tried to build PHP, with MySQL support, or did you install a binary? If you did try to build it, how difficult was it? I'm wondering what we can learn from the PHP install process.
PHP is about as difficult to build as perl and DBI.
I'm pretty confident that anonymonk's problem is that he did not build his own perl and thus his current setup is lacking critical components (typical of macperl).