Yadex is a Doom level (wad) editor for Unix systems running X, including Linux. It supports Doom alpha, Doom beta, Doom, Ultimate Doom, Final Doom, Doom II, Heretic and also, in a more or less limited way, Hexen and Strife. It is available under the terms of the GPL. Fun stuff.
Created attachment 23522 [details] yadex-1.7.0.ebuild
Added to CVS. Thanks for the bug report and ebuild.