Hi Cash,
I think you may be hitting bug CSCsb12946 which prevents this feature from working.
You require at least CCM4.1(3)SR2
Set enterprise parameter (System->Enterprise Parameters->Cisco Support Use 1) Cisco Support Use 1 to CSCsb42763 (case sensitive)
This operation added listbox (Route Plan->Route/Hunt->Hunt Pilot->hunt pilot XXXX -> Call Pickup Group) Call Pickup Group.
From this doc;
http://www.ciscotaccc.com/kaidara-advisor/voice/showcase?case=K11612191
Hope this helps!
Rob