Problem in using use cases in seq diag with VSS

[Roger A. Shepherd]

Hi,
I created a bunch of use cases that are the capabilities of the system we have.
This bunch of use cases should act as a catlog for various sequence diagrams that we create in order to do system integration.
This catalog is under VSS, so when another person tries to create a sequence diagram by dragging a use case into it (as a link) - there is no problem.The problem occur when the user tries to add a message from a use case to another - the error he gets is "warning - Connector cannot be created.Source element is locked or checked into version control.
this is makes sense, because teh action of adding a message between elements creates a link in the element itself.

My question is:
1.Is there a way to solve this problem and still manage this catalog under source control?
2. If the answer to 1 is no, is there a way to do it in another way so I will not have this problem.

Thanks a lot,
Guy.