Lenny - I got the 4.2 version here for Verizon:
http://imnuts.hostedwith.us/?page_id=3 my only modification of that file was to add my number to the X-VzW-MDN key.
I'm using textpad to modify the rgu file and there doesn't seem to be a change in size - I've also tried notepad. Is there another app I should be using instead? Maybe that is the issue after all....