SMS sent/received - TESTED
MMS sent/received - TESTED
Remember, what you do is at your own risk, I am not responsible for anything.
Be sure you make a nandroid backup, of course and root is required.
To mount \system folder:
1. Reboot into recovery mode (Power device down then hold power button + volume - or optical key instead of vol -)
2. choose partitions
3. choose mount \system
Navigate to C:\sdk\Tools in a windows command prompt
adb shell /system/bin/rm /system/app/Mms.apk <<<<<<<<<<<< File name must match file.
Remount system when complete and reboot.
Attached file is the Vanilla mms.apk, install it when you reboot your phone.
All text messages should be saved, FB integration is still there.
Side note, with the stock mms.apk removed you can use just Handcent for SMS, but MMS won't work.