DirectFB backend is supported in >=x11-libs/cairo-1.1.x. Please refer to; http://cairographics.org/news/cairo-1.1.2 I thought it would be a good idea to have a directfb USE flag, and came up with the attached diff file. (It's my first ebuild modification, so it could look messy. At least it worked for me with dev-libs/DirectFB-0.9.25.1 ebuild.) Thanks in advanced.
Created attachment 88638 [details, diff] directfb USE flag added diff. an ebuild diff with x11-libs/cairo-1.1.6-r1.
Fixed