Russell and holmes4, I'm not really sure. Our SMS solution is using Syniverse which is the major SMS partner out there. If you guys want, you can try sending a test message to my test account number 3047096900 (it'll just go to me so it's safe) and I can let you know if I receive it.

We've tested with all the major cell carriers, but there may be some smaller ones that don't support it.