Thanks, I came here just to look for something exactly like this. I'll let you know if it blows up my phone (Don't worry, I know how to recover it).
First thing I tried doesn't work. Its an issue with AOSP and Verizon (CDMA?). MMS won't send if you are connected to WIFI. The MMS needs to go through the 3G/4G towers and the switch to 3G/4G doesn't happen. You need to manually turn off WiFi for it to work.