I tried to upgrade gtk+ but got the following error: configure: error: pangoxft Pango backend found, but Xft not found although I had pango 1.0.5 installed. after upgrading pango to 1.2.0 I was able to emerge gtk+ with no trouble.
Then your 1.0.5 was built without xft backend... it shouldnt be..must be some old xfree leftover.