i have been switching back and forth between roms oN my VX6700 on verizon trying to figure out wtF the issue is with sending & receiving MMS. i has Helmi's 6.1 installed and could never get it to work without the aid of wi-fi connections(ie, hotspots, wireless networks). but i think i figured it out.
i have a version of WM6.5 installed on this now (CE OS 5.2.21501(build 21501.5.0.70). initally i was unable to get mms from this phone at all. after hours of fiddling i gave. until while bored at work the other day i searched online fourms again and found this thread
http://forum.ppcgeeks.com/showthread.php?p=1122252
i downloaded the verizon cab and installed it on the phone. still, to my dismay it did not work. i would continue to get the message "originator address not found" i couldnt find any soultins for this problem. so i deceide to download a registry editor and see if i could see where some info was missing from the keys. honestly i have little knowlage of editing registry keys,so fumbled around for a bit looking for something that would seem to me like an address , or something descibing my number in the arcsoft software....
i navigated to this
hkey_local_machine-->
software-->
arcsoft-->
arcsoft mms ua-->
config-->
mm1-->
wspheader->...from there again i really didnt know what to put anywhere or what to change,but i noticed the entry"
x-vzw-
MDN" said "mynumber" so changed this to my number(with no dashes or spaces), soft reset the phone and
IT WORKED!!!!!!!!!!!!!
i re-flashed and went throught the set up againwith a newer version of Arcsoft that wasnt verizon specific, and i didnt work. the "x-vzw-MDN" was not there, and i could find nothing that looked like it would take my number. so re-installed the older version of arcsoft and it worked again.
make sure to set up your access to dail #777 and it should work fine hopefully this will save someone the 4 days it took me to get this hammered out.