If you're on Sprint and you have a CDMA device, then this is the .CAB you're looking for. this will install (2) icons in your systems-->settings tab. One will be 'Update PRL' and the other 'Update Profile'. I used these myself after flash to MightyROM one time (before I had data service active on a new device) and this fixed all the problems. Hope it works for you.
Direct Link:
Sprint-Update-Profile-&-PRL.cab or attachment below: