Anthony,
It should be like this:
GK1#sh gat en
GATEKEEPER ENDPOINT REGISTRATION
================================
CallSignalAddr Port RASSignalAddr Port Zone Name Type F
————— —– ————— —– ——— —- —
10.1.5.171 1720 10.1.5.171 1150 GK TERM
E164-ID: 0207880800
10.100.135.73 1720 10.100.135.73 57604 GK VOIP-GW
H323-ID: GW1
Total number of active registrations = 2
Or are you using an interface on your 3640,it also helps to reboot after some config changes.
niek.