The line in this file is: :0 local /usr/bin/X -vt 7 This breaks the system if your X is not on vt7. Just omiting this option makes X work fine.
I've added some more comments to /etc/conf.d/xdm about this (/usr/portage/x11-apps/xinit/files/xdm.confd), they'll show up in an hour or so. Basically, yes, it is hardcoded and will stay that way, because it's required for large speedups in when you get a login screen. People who don't want it hardcoded can remove it manually.
Only one thing is missing, then. Say so in the documentation. I've spent 3 days in debuging my keyboard and searching for tutorial/howto/solution of any kind. Thanx! :o)
/etc/conf.d/xdm _is_ the documentation, and should be the natural place to look to configure xdm.
I`m sorry, you`re right. I wasn`t looking. My bad. :o(