Deployer cannot delete Broker document when doing Rollback .. ?!

I’m experiencing a problem in using Deployer … I tried deploying my project from Development Server to Production Server using Deployer package, and there were problems … Now when I tried doing a Rollback in Deployer to undo the changes made on the target server, none of the Broker documents from the target server are deleted because of errors such as this:

Could not delete the Broker Document Type named “wm::is::ARS::docTypes::ARSWrapperNew” due to an exception: Operation failed because permission is denied. This operation requires administrative permissions.

There are 20 or so such errors, each with a different document name mentioned …

Can someone tell me what might be causing this ? … To what do I assign privileges for this to happen, and how ?

Really need help here from someone …