@openmedia: Not sure I really understand all the APN settings, but I wonder if setting TelecomData to "internet + mms + dun" without providing any MMS settings might break MMS on that APN? I don't use MMS, so I don't care, but just noting it in case anyone else reading this does.
I interpreted openmedia's post as 'try removing the +dun from the TelecomData APN settings and see if that works', is that what you meant?