I have a Cisco 2501 connected to an Astrocom SP100 to a frame connection. Whenever I try to bring the line up I get a "Serial1 is up, line protocol is down" message on the Cisco. I have insured that both Ciscos have an LMI type of cisco but no good. When I tyurn remote loopback on the one Astrocom the Telco says they can't see it. Would they be able to see the loopback?