ATM-Port Sync failed ... but why ?

[martin.loose]

A Cisco 876w Router should work as VPN-Server and Gateway. Everything is set up well, but the Router cannot sync the ATM-Port with the ISP`(german telecom). Two different ports are tryed out, two times with the same result -> no sync. Arcor as my private ISP has no problems to sync the device, why doesn't it work at the telecom-port ? Could there be different default values or protocols ?

May you have some ideas ?

[a-vazquez]

Under heavy traffic, a port adapter might experience a SAR0 reload. If this condition occurs on a Cisco router, you must reload the router to recover normal operation. This situation might result in commands from the RSP to the port adapter failing, but the port adapter should be able to recover without a router reload