Is Digi XBee Zigbee Modules (SMT) in Zigbee Development Tools (802.15.4) Zigbee Mesh Kit WorldWide is programmable?

I’m planning to buy a Networking Modules XBee Gateway ZigBee to Ethernet/WiFi Int and Zigbee Development Tools (802.15.4) Zigbee Mesh Kit WorldWide to built the nurse calling system. I want to know whether that Zigbee Gateway works with the Mesh kit. And also Digi XBee Zigbee Modules (SMT) in the Mesh kit is programmable or not?