Gnome 2.22.1.2 crashes if /etc/timezone is missing and the /etc/localtime is a normal file. gnome-panel doesn't crash if /etc/timezone is a symlink to /usr/share/zoneinfo/YOUR_TIMEZONE.
Created attachment 150251 [details] emerge info.
2.22.1.3 has another bunch of fixes for timezone stuff. Could you bump the ebuild in a local overlay and let us know if it fixes your issue? If not, it might be a good idea to file a bug upstream. Thanks
I bumped gnome-panel to 2.22.1.3 and it did fix the problem.
commited 2.22.1.3 to the tree.