This is very due able. I was able to take my existing VoIP solution at the house to include; Cisco router w/FXO, Cisco inline pwr switch, Call Manager 3.3(4), Cisco PAP2, (3) 7960’s, (4) 7940’s, and my personal favorite (1) 7970, and successfully make calls from my VoIP phones thru the Call Manager and out my Vonage PAP2 using h.323. I am still tweaking the config but it works like a champ. More to follow…
for more info…
Vonage VoIP Forum – Cisco Call Manager Express, UNITY and VONAGE integration