There is no support for epatch_user, please add it
Added package maintainer to CC.
Fixed in overlay
commit 5351eecfac7831fe3e7ffabbb8a644eca6a84cf2 Author: Azamat H. Hackimov <azamat.hackimov@gmail.com> Date: Sun Jun 16 08:02:14 2013 +0600 [media-libs/libsdl] Added epatch_user (#473252) Package-Manager: portage-2.1.12.2 Manifest-Sign-Key: A018DE8C