Can asterisk register as a SIP endpoint to a Inter-tel 5000

Does anyone know of a way to allow Asterisk to directly interface with an Inter-tel 5000? I was hoping to use an IP protocol instead of some kind of a T or POTS line. If not, does anyone have any suggestions on how to at least get number dialed (should be CID 4 in Hylafax) to be passed from an Inter-tel 5000 through POTS?

Changed title to hopefully be more accurate.