Automation error The application called an interface that was marshalled for a differ

Hi,
My Web application works fine in Win NT environment(IIS 4.0, MTS server for COM components). When i moved my application to windows 2000 server along with MTS components to Windows 2000 server i am getting the automation error when multiple users are in
"The application called an interface that was marshalled for a different thread."

Any help would be greatly appreciated.

Thank you
hanu