asterisk users - May 2004 - mgcp with busy tone

Hi there,

::: i have an mgcp phone (iph-90) using the sample mgcp.conf for it 
(the dlink section). i've tried both asterisk stable and development 
release but i'm getting the following error when i lift the receiver:

. .. in stable branch:
  -- MGCP mgcp_new(MGCP/aaln/1@gw52302432-1) created in state: Down
while the phone is giving me busy tone

. .. in development release:
chan_mgcp.c:2227 handle_response: Terminating on result 502 from 
aaln/1@gw52302432-1

while the phone after a "short beep" giving me busy tone too...

any ideas?

wiking