Fiber Issue

We are putting up a new building and have run fiber between the new and the old.  I have a Cisco 2821 with a fiber interface and a GBIC at one end and a HP2848 with a GBIC at the other end.  Both are set to 1000DX.  We can't get the connection to come up.  We get line protocol down on the Cisco side and the GBIC interface is down on the other side.  We have a seperate network of fiber that goes between the buildings(Our test network) that goes from HP GBIC in a 2848 to a HP GBIC in a 2848 and that works fine.  We are using the router on the first network because we are trying to ties two subnets together.  Happy to supply router config if needed.