B2B Server dies frequently

We are running B2B Server 4.0.2 on windows 2000.
Every time we start the B2B Server it dies after a short period of time. The license keys are valid so that is not a problem. Looking at the console log the last display is always:
000B18 [B2BSERV.0003.0002] Checking for expired webMethods B2B server sessions.
Also, There appears to be a correlation between leaving B2B Administrator running and it’s unexpected termination. It appears that WM dies sometime shortly, say an hour, after the B2B Administrator session is closed.

Pls contact the webMethods Tech Support,since this issue might be related to license or might be the server itself.

Thanks.

The problem has been resolved by running the server as a window service. The problem was that the user was accessing the server using windows terminal services and then starting the server from the console. Once the user exits the terminal servicesm the terminal services the server is shut down by the windows, when window attempts to do a cleanup (as from the windows perspective the user who has started the script has logged off). So we changed it to run as a windows service and its fine so far.

Thanks for your help.