"You kernel source contains an incompatible version of the" should be "You*r* kernel ..." Reproducible: Always Steps to Reproduce:
Hmm, I've lost my crystal ball... which ebuild is this about?!
Sorry about that, it's in the net-wireless/ieee80211 ebuilds. Affected versions: ieee80211-1.0.3-r2.ebuild ieee80211-1.1.5-r1.ebuild ieee80211-1.1.5.ebuild ieee80211-1.1.6.ebuild
Thanks, fixed in CVS.