Hi! I created an ebuild along with a patch for the Makefile for the latest release (0.6.4, 2006-02-10) of chan_capi-cm. Tested here on an AMD64 with asterisk-1.2.4, it works allright.
Created attachment 79466 [details] asterisk-chan_capi-cm-0.6.4.ebuild
Created attachment 79467 [details] chan_capi-0.6.4-gentoo.diff
chan_capi-cm-0.6.4 has been moved from the gentoo-voip overlay