I'm pretty sure you can just turn off MMS retrieval, yeah -- either in your messaging app or the phone's network settings. The only problem is that many phones

I'm pretty sure you can just turn off MMS retrieval, yeah -- either in your messaging app or the phone's network settings. The only problem is that many phones automatically turn long SMS messages into a single MMS message. As I understand it, you might not receive those -- although I'm not sure about this.