edit.... here are the instructions.... add the following repo in Cydia.. http://c.ifon1.no/ it took me 2 to 5 times for it to finally recognize the url, but it did (not sure if thats my wifes phone or the repo's server or our wifi). once that is done, go back into sources and view all files available for the ifon1 repo. choose the obvious one, 2g MMS on 3.1.3 again, it may take a few attempts to download the file, again, not sure if thats the repo server, my wifes phone, or our wifi. once you are done with that, you will need to MAKE SURE MMS IS TURNED ON IN THE MESSAGING SECTION IN SETTINGS. then you need to go to Settings>General>Network>Cellular Network... change the MMS setion to the following... APN: wap.voicestream.com or epc.tmobile.com or wap.tmobile.com (depending on your data plan) Username: leave this blank Password:leave this blank MMSC: 184.108.40.206/servlets/mms (the ifone1 repo file automatically adds "http://" to the front, you will need to delete the whole line and retype in the same info but with out the http:.// in the front MMS Proxy 220.127.116.11:8080 MMS Max Message Size:leave this blank IF YOU CAN, if not, change it to 99999999 (that would be 8 9's) MMS UA Prof URL:leave this blank IF YOU CAN, otherwise, leave it alone. my wifes phone settings are.... APN - wap.voicestream.com MMSC - 18.104.22.168/servlets/mm MMS PROXY - 22.214.171.124:8080 MMS MAX MESSAGE SIZE - 99999999 MMS UA PROF URL - HTTP://WWW.APPLE.COM/XXXXXXXXX (X = SOME OTHER STRING OF LETTERS THAT I DONT HAVE IN FRONT OF ME RIGHT NOW). now do a FULL REBOOT of the phone. now it should all be working. test it by sending someone else a pic and then have them send one back to you. by sending yourself one, you are not going through the "complete" channel of mms "delivery" and is not an accurate way to verify you are working correctly. hope this helps!!!!!!!!!!!! i had originally posted this thread for more info to get this working for people still on a 2g w/ 3.1.3 and never got an answer. well, i stumbled across some info last night and found a repo for the needed file. for those that are interested i have found the answer and it was tested on my wifes 2g iphone last night and is 100% working with ZERO downgrade to the pictures (they are sent at full res). i am going to do this on a buddies 2g iphone w/ 3.1.3 and see if it works as well. ill report back in a couple hours with the "how to" in a couple hours.