Found it!

This is the fix right here:
Solution ID: NORT195876 Product Family: Enterprise Voice Create Date: 01/26/2005
Title:
Inbound PRI trunk calls with DNIS = YES are answered and transfer fails to connect to proper mailbox on redirection to CallPilot.
Facts:
Core
Release 2.02
CallPilot 2.02
CP 2.02
Symptoms:
Inbound PRI trunk calls with DNIS = YES are answered and transfer fails to connect to proper mailbox on redirection to CallPilot.
Cause:
CallPilot patch CP202S03R21S loaded on CP 2.02
Fix:
Install MPLR18136 on PBX (refer to readme text on CallPilot patch CP202S03R21S).