Seems no one had created an ebuild for the Perl module Tk::JPEG. Here's a basic one. Reproducible: Always Steps to Reproduce:
Created attachment 15948 [details] Tk::JPEG ebuild
Does this module add support for any existing or proposed ebuilds? Gentoo policy at this time is not to add perl modules unless they are a dependancy of another package - otherwise we recommend installing yourself from CPAN.
http://www.gentoo.org/doc/en/policy.xml#doc_chap2