You are looking for to delete the cached password stored by CVSNT in the registry editor ??, This is your solution !!, this is a Registry Monitor designed for this, monitor a registry key and delete it after a configurable time.
syncmail is a CVS notification tool which can provide a diff for every change to a CVS repository, mailed to specified email addresses. This tool is useful for large communities to monitor activity, and is used for Python and many other active projects.