DI Server - Update Service call

Hi All,

I am using DI server to update a service call. This service call has an activity attached to it. Now i am trying to add a new activity to this service call. the following error is reported.

Removing activities from service call is not allowed. [OSCL.customer]

without activity i am able to update the service call.

Any help would be appreciated,

Thanks & Regards

Amudha