we have a Voice over IP connection to some offices abroad which are on both sides connected with a Cisco router via an E1 connection to an Ericsson MD110. It used to be a 3725 with IOS 12.2(13)T16 on both sides. Since we upgraded to a 2811 with 12.4(13r)T on the remote side, when ever a call is transferred on the remote side or an automatic diversion is set, we get a disconnect. ISDN debugging showed the error message: "Mandatory information element missing", see the attachment for full output.
Any ideas on what might be missing and what might be a workaround?