Problem with T1 interfaces on a Cisco 2951 router

I'm having a major problem with a brand new Cisco 2951 router.  The router is going to replace a Cisco 2811.  Currently there are two P2P T1's connected to the 2811 configured with ppp multilink.  When I move the circuits over to the 2951 they remain in a down / down state.  If I loop the T1 controllers on the 2951 (via the "loopback local payload" command") then remove the loop the T1 circuits will come up and I can ping the router on the other end of the links.  The problem is if the router is rebooted both circuits remain in a down / down state until the controllers have a loop applied then removed.  I'm baffled as to why this is happening.  The links are connected to separate VWIC's on the 2951 so it can't be a bad card since the problem is occurring on both.  When the circuits are plugged back into the 2811 they come up and work perfectly.  It is not a TelCo issue, it has to be something with the 2951.  I have verified that the controller and interface configuration is identical between the 2811 and 2951  Both routers are configured for - Framing is ESF, Line Code is B8ZS, Clock Source is Line.  The router on the other end of the circuits is configured the exact same.  I have no idea why the circuits won't come up on the 2951.  I don't understand why they will work if they are looped then unlooped.  Unfortunately they won't stay up.  I have tried both the 15 and 15.1 versions of the IOS.

Can anyone provide any insight as to why this is happening?  Any assistance would be greatly appreciated.
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steno1122Author Commented:
Received help outside of this forum which resolved the problem.  Closing case.
atlas_shudderedSr. Network EngineerCommented:
Have your thrown a loop from the smartjack back to your routers?  If so, what are the results?
Have you validated that telco is providing timing?  If not, try setting timing to internal on your near side and post results.
Can you post a show int for both the routers?
Can you post a show cont t1 for both?
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