The Mesa-3.4.2-1 package recently posted to Rawhide depends on XFree86 4.0.3, which makes it incompatible with the current Rawhide XFree86 package.
I challenge you to _really_this_time_ look at rawhide.redhat.com ... Surprize! It's Mesa-3.4.2-0.410.2 out there. The version you have is from M. Harris' personal site, which is not rawhide. Close you bug please.
That's right - Mesa 3.4.2-1 is built against 4.0.3. The Mesa package and the XFree86 package are tightly coupled. You cannot upgrade one package to a newer version without the other. The current Mesa package for 4.0.3 is -1, while the current package for 4.1.0 is 0.410.*. Right now what should be in rawhide is Mesa 3.4.2-1 and XFree86 4.0.3-22 or -23. XFree86 4.1.0 has been removed from rawhide temporarily due to some font related issues that need solving before widespread testing.