iPhone used as a call centre agent phone

[cmac]

Does anyone have any experience using an iPhone as an agent phone that Genesys will route calls to? 
We have a Cisco/Genesys install, we can get the iPhone to register with Cisco, but rather than passing a MAC address to Genesys, a Device ID is passed instead.  Genesys TServer can see the Device ID (in Genesys logs) but doesn't know how to interpret it, doesn't recognize the iPhone as an end point.  Is there a certain parameter that needs to be set in TServer?