I have no idea why. I upgraded from 1.26 to 1.27 when this happened (my webserver started spitting out that it could not find Apache.pm and similar). And since the 1.26.ebuild file is gone, I am having trouble to reinstall the previous version and figure out the differences. Anybody?
Seems the problem was with perl itself (found stuff about it in the forums). Sorry.
just re-emerge perl-5.6.1-r7 and then re-emerge mod_perl