It is possible to put system together to send an email alert, once you have email capability you can send a text message via email.
The pieces I'm putting together is AHP running on computer running 24x7, CM15A (receives X10 power line commands lights on/off sequence from the SC1200 during alarm trigger), modified X10SW which is not currently available (see
http://forums.x10.com/index.php?topic=17541.0), and email script. The author of X10SW Tuicemen is looking into adapting the program to work with the SC1200. Finally, You must be a dedicated tinkerer to go through all this trouble. Additional notes; X10SW requires only SDK and AHP is not requirement.
It confounds me that this feature not built into AHP and OnAlert
If you have an old wireless laptop around, it might be easier to buy magicjack voip and use that as dedicated alarm phone line (this is what I have right now.) to get the alert and remotely arm disarm the old fashion way. You can replace the magicjack/laptop combo with VOIP ATA device/ethernet/wireless bridge