Callback from a Linux to Cisco as5300

[roliveira]

Hi

We are trying to put a Linux box doing callback with a cisco as5300 using an ISDN interface. When a packet arrives to the Linux box, the Linux calls the a phone number where there is behind a cisco as5300. The as5300 breaks the call down
and callback the Linux. At that time the communication does not
proceed because the as5300 tries to negoatiate the callback with the Linux but apparently the Linux does not understand
this negotiation step.
Any tips, about what to do in the Linux box or in the as5300 side?
Best regards
Raul Oliveira