Can not check in or check out in the workbench

We have set up a new installation of LiveCycle ES4 with SP1 on weblogic. Everything seems to be working fine but we can't check-in or check out files.

Actually, a new file can be created and checked-in to the repository for the first time. If you want to make changes to the exsting files, the CheckOut functionality is not working. When I checkout the resource, I am not getting the icon to show the resource was checked out. And the Check-In option is greyed out.

There is no error message (nor popup, nor specific line in the logs)..

Does any one has experienced the similar issue..

Thanks

Srini