IAX2 Not processing CALLING NUMBER

The calling number is being passed by the carrier to our box (as per debug below):

Rx-Frame Retry[ No] -- OSeqno: 000 ISeqno: 000 Type: IAX Subclass: NEW Timestamp: 00009ms SCall: 00001 DCall: 00000 [A.B.C.D:4569] VERSION : 2 CALLED NUMBER : 617NNNNNNNN CODEC_PREFS : (ulaw|gsm|ilbc) CALLING NUMBER : 07NNNNNNNN CALLING PRESNTN : 0 CALLING TYPEOFN : 0 CALLING TRANSIT : 0 CALLING NAME : LANGUAGE : en USERNAME : NNNNNN FORMAT : 4 CAPABILITY : 4194303 ADSICPE : 2 DATE TIME : 2010-04-06 03:26:16

But for some reason - it is being entirely ignored as per:

Running Asterisk 1.4.30 and Addons 1.4.10 with a realtime MySQL config.

I don’t even know where to start looking to see where the CALLING NUMBER is being lost.