In the VDS control panel, when clicking on the "manage users" link in FrontPage administration page a login pop up window is displayed, and its impossible to login because the user and password of VDS owner are not accepted.
The option to manage users via VDS control panel is disabled by default.
In order to enable this option for VDSs, please do the following:
1. Login to machine where SD is installed.
2. Open "Microsoft SharePoint Administrator" window from Start --> Programs --> Administrative tools --> Microsoft SharePoint Administrator.
3. Click on "Set list of available rights" link
4. Web Administration Rights section, select the relevant checkboxes for enabling users management (the first two checkboxes and click the "Submit" button.
After performing those steps VDS owners on this Server should be able to manage users in FrontPage.