Hi henjoh,
Are you using the physical DBC IP-phone or ECC or another H.323 software?
Anyhow, first make sure that the network where your ELU32 and your client are supports multicast. No multicast, no discovery, this can be a problem if you have routers in between.
In the MD110 make sure you have set the GKID parameter to something. E.g.
IPGKC:LIM=1,GKID=SOMETHING;
Then in your software set the gatekeeper identifier to "SOMETHING".
If you are using the DBC IP-phone set the GatekeeperID
value to SOMETHING and GatekeeperDiscovery=YES in the
IP-phone.cfg file which are loaded as you boot the IP phone.
Did you get it to work?
/mk