Today i had a problem where i couldn’t send MMS messages using my HTC Desire Z Android phone. Im currently running Cyanogenmod 7.0.3 so i went looking for a fix.
This is what worked for me:
1. Download root explorer (It costs a few $ from the market, but well worth it) or an equivilent and give it root priviledges.
2. Locate the following file, telephony.db: /data/data/com.android.providers.telephony/databases/telephony.db
3. Rename the file. (e.g xxtelephony.db.xx) or delete it (I deleted it)
4. Restart your phone
5. Now try sending an MMS.
That solved my problem and i can now send MMS messages again. This fix may also work for other roms, so give it a try if you’re experiencing problems.