unless there is some way of getting the cisco ip phone in voice vlan without cdp?
The cisco phones do support Passthrough for EAPOL
and Proxy EAPOL-Logoff.(unicast only i think) I don't think these mechanisms are tied to using cdp, but you need to get the cisco phone into voice vlan first. true phone supplicant support is the only way to go, and i don't think cisco is going to be offering it in the near future. Hope you folks are :)