I have been having the same problem for the past 2-3 weeks. My co-workers have all been having the same problem, too. One of them is now using a personal VPN to connect, and he states there is no problem now. Personally, I have had to start using Skype more often, and that has been working fine for me.

Roots, what ip addresses are you using to tracert and ping to when testing with Vonage?

I'm glad to see that VoIP is allowed because after the incident in 2005 we were all wondering if they were blocking it again, too.