Call time expired

One of our customers uses a Notes Client on his notebook. He makes a call directly to a Domino server. The Notebook is a Toshiba SP2100 with a Toshiba Software Modem AMR. In the Notes client, the modemfile Toshiba Internal Modem (V.34 28.8 Data + Fax + Voice) is used.On the server is a USRobotics Modem 56k. This modem works fine, because I am able to connect to the server from a desktop with a modem.

When the users calls the server, a connection is made (seen in the server’s log) and after ca 1 minute he gets an error: Call timer Expired. In the server’s log: Modem lost carrier.

When the user tries to connect again, the connection is made without problems.

Client’s OS: Windows XP prof.

Notes: 6.01CF1 (server and client)