Iran has notoriously bad SMS networks. They're always dropping out when you need it most. Iranians in the cities love using Bluetooth to send messages and pictures to each other, and many have sophisticated mobile devices.
A more robust system for SMS could bypass the carriers and use a peer-to-peer mesh network in cities to send SMS messages. Everyone running the SMS software could forward messages and, in a large city, with lots of mobiles, it could get to the recipient quickly.
That's the idea, anyway. Some very smart Iranian computer scientists (and there are enough working away on open-source projects and new solutions to the network access problems) could find this an interesting problem to solve. Heck, they could even bake-in encryption from the get-go.