... and everybody complained it didn't work.
Here's the deal:
There are two ways to use mod_perl in Apache... statically linked, or dynamically linked.
I always use the static version for speed/sanity/safety, but I figured, "oh, Debian would manage to get the dynamic version right.". So I put it on goathack.
But it doesn't seem to work. At least not in unstable.
So... to get stuff working:
-- do everything Opi said in that link above
-- but, don't add the LoadModule perl_module line
-- apachectl stop
-- apachectl start
Goathack now only has the apache-perl package installed, and then some symlinks. Have fun.