$ equery f avidemux-plugins|grep '\.py' /usr/lib64/ADM_plugins6/autoScripts/720p.py /usr/lib64/ADM_plugins6/autoScripts/PSP.py /usr/lib64/ADM_plugins6/autoScripts/check24fps.py /usr/lib64/ADM_plugins6/autoScripts/dvd.py /usr/lib64/ADM_plugins6/autoScripts/lib/ADM_image.py /usr/lib64/ADM_plugins6/autoScripts/lib/ADM_imageInfo.py /usr/lib64/ADM_plugins6/autoScripts/svcd.py /usr/lib64/ADM_plugins6/autoScripts/vcd.py Seems like you need to use python-single-r1.eclass
+ 01 Sep 2013; Tom Wijsman <TomWij@gentoo.org> avidemux-plugins-9999.ebuild: + Preparation for 2.6.5, make use of python-single-r1 and fix up shebangs, fixes + bug #467254.