x11-terms/rxvt-unicode ships internal version of libev
looks like to be a pre 4 version of libev which is bundled.
*** Bug 344099 has been marked as a duplicate of this bug. ***
Created attachment 255419 [details] files/rxvt-unicode-9.09-libev.patch Works only with USE=-perl. I don't have a clue how to fix this.
With rxvt-unicode-9.14, a libev-4.10 Changes files is shipped in libev/, so maybe it would be just as insane to try to link to the system libev as it is to unpack dev-libs/libev from the rxvt-unicode sources. :)