Couple of questions:
1. what version of CCM are you running?
2. Is the GW set to receive 4 significant digits?
Try doing the same with an IP phone, and if that works use the same CSS/Partitions combo for the RP
Make sure the CSS on the callForwardAll field is correct.
Also, instead of the CTI RP try using CTI Port.
Post your CCM trace after you make a call, specify what you dialed and where is it supposed to forward.
Chris