What is the easiest (and least expensive) way to add SIP- or IAX-compatible stations to an Elite IPK system? I would like to add users at a few remote offices to our system rather than having each remote office with it's own local and 800 numbers.

My NEC vendor said that the IPK can support VOIP trunks but not stations.

I have 8 analog ports on the system. If I had to, I could run four of those out into SPA-3000 FXO's, and use them as incoming lines for an Asterisk server, and have all of the remote users set up as extensions on the Asterisk system. The problem I see here is how to get Busy / No Answer calls sent back to the voicemail system in the IPK.

Any suggestions would be appreciated.

MT