You may try U.C.ME-OPC from Control-See (see www.controlsee.com ). It connects to WinCC using OPC or DDE and send an SMS using a cellular modem (Siemens, Wavecom,...). Alarms may also be acknowledged by the recipients. In addition, you may send an SMS command from your cell phone to query or change a tag value.
A fully functional evaluation version can be downloaded at www.controlsee.com .
Mike
Alarm Control Center (ACC) is a best tool. But if you want to use another (cheap/simple) application, you can follow these 3 steps :
1. create exe application. *i create Send_SMS application, you can download it.
2. edit Alarm Logging and check Trigger Action.
3. edit script of GMsgFunction.