The infamous dev-team has just released an update to ultrasn0w for those running firmware 3.1.x with 04.26 baseband. The update fixes the issue of missing carrier logo from the upper-left hand of your home screen.

This is the official word on the dev-team blog:

Today we released an ultrasn0w update that fixes an issue for those running firmware 3.1.x with the 04.26 baseband.  That specific combination resulted in a missing carrier name in the upper left-hand corner of your home screen.  Today’s ultrasn0w update from 0.91 to 0.92 fixes that problem (which was an important issue for roaming). You should see the update available if you have http://repo666.ultrasn0w.com as a Cydia source.  Enjoy!