Audio-CD-disc-cover-0.04 gets installed as a dependency for disc-cover. The problem with the current ebuild is that it installs the modules under /usr/lib/site_perl/5.6.1/i686-linux/[...] while the "right" (i.e. searched) path for perl modules under gentoo would be /usr/lib/perl5/site_perl/5.6.1/i686-linux/[...]
Please try again. The corrected perl-module.eclass was uploaded last night and should be propagated out by now. emerge rsync (--clean rsync if you haven't upgraded your portage recently, clean is inherited now by default) and let me know if it doesn't work right still. Thanks!
If this is still an issue, please let me know, otherwise I will close this as fixed.
Testing for the new eclass is done, all modules and packages have been updated, and this has been commited. Thanks for your patience, Michael