Adding "export WANT_AUTOMAKE=1.6" in the head of the ebuild solve the problem.
Created attachment 98937 [details, diff] kbfx_ebuild.diff "head of the ebuild" was a bit too unprecise so here's the patch that makes kbfx compile again... Cheers Poly-C
Thank you for your patch. Fixing this correctly required a few more lines though, as you might see in the ebuild. Thank you for reporting this. Fixed in CVS.