Here is a thread where I helped a couple other guys. Wireless, Battery Operated Wall Switch I wrote a custom device type for the switch and you guys are very welcome to use it. Look in the thread and you should see the code. You can cut and paste that into your IDE and assign it to your 3 button switches.
Just as an FYI this switch can also do a direct bind to an on/off ZigBee device. You can use this to have it directly control a light or wall plug (must be a ZigBee device to do a direct bind) Take a look at the instruction on how to setup a device bind that came with the switch. The cool thing about a direct bind is when you push the button the command goes directly to the bound device. The SmartThings hub is not required for the command to be successful.