Dialing out through Norstar

My client has a 20 year old centrex which i’m trying to integrate with trixbox. They would like to retain the old system until the trixbox is proven. Dialing out through it is the best way i can see to do this. I have a tdm01b to work with, and i don’t know how to get an outside line. My trouble is that there isn’t a dial tone on the lines i connect the fxo to. Users press Line 1 or Line 2 to access a line with the existing phones. Is there documentation on these somewhere? Do i have to rewire something? Any help would be greatly appreciated.

Nortel Meridian Norstar KSU