[Asterisk-Users] Using a TE405P to connect to an existing PBX

[drodden]

We originally purchased a TE405P so we could connect our Asterisk server
directly to the T1 PRI from our provider, however due to all the
problems reported with T1 PRI's interacting directly with Asterisk, we
scrapped that idea and decided to stick with our Cisco router making the
conversion to SIP. 

Anyways, we found a new potential use for it. We have an old location
with an existing PBX, and they want to be able to "share" our PRI's here
and make calls to our location without tying up phone lines. Their
existing PBX system has 2 PRI's from some telco running into it. If I
put 1 or 2 TE405P's inside a decent machine, can it "trick" their PBX
system into thinking it's talking to a standard PRI? Essentially be a
FXS port instead of an FXO port? Looking at the zaptel.conf file and it
seems as simple as using fxoks vs fxsks? And then using a T1 crossover
cable to get a link?

So then as far as their PBX is concerned, it's talking to a real PRI,
but then the Asterisk server would take it and convert it to IAX
(possibly with trunking to save bandwidth) and send it off to our
Asterisk server here. 

The documentation I've found on configuring a TE405P isn't very
detailed, does anybody have a link to some more in depth instructions
with lots of examples? Do you recommend 2 cards in one server, or 2
different servers?