There isn't any support with AT&T CallAvantage...
I just signed up and receivd my TA and it doesn't work. I called tech support and they couldn't do anything for me and said that they will have escalate my issue to another higher tech to call me the next morning. They didn't call and I called back and they said they will contact you in 48 hours. Still no call back.
I'm going to cancel my order immediately come Monday.
jt