after a fresh install I pulled xorg-server-1.7.3.901-r1. It failed at configuration time:
checking for GL... configure: error: Package requirements (glproto >= 1.4.9 gl
>= 7.1.0) were not met:
no gl package found
===
I tried to set the minimal flag to compile xorg-server and then merged mesa-7.7 but mesa failed (of course).
So I tried to pull mesa-7.6.1 which worked on a minimal xorg-server (this version does not explicitly depends on xorg-server[-minimal] as 7.7 does).
Then I remerged xorg-server-1.7.3.901-r1 which worked and I remerged mesa-7.7 which worked.
All is fine now but I banged my head for an hour.
erick