Screen sharing to OS X Lion Server with non-admin account
I have set up a Lion Server with one admin (in addition to the root user) and several non-admin normal accounts. In Server.app, I have enabled remote login with ssh, and remote management via screen sharing. I am unable to use Screen Sharing to connect to the server from the non-admin accounts, but able to use the admin account. I've read that it is only enabled for admin users, but need to access from non-admin accounts, and I can't add these accounts to the admin group. Is there a way to do this with Workgroup Manager? I tried changing the Remote Management settings in System Preferences by adding the non-admin, but when selecting 'Observe' and 'Control' in the options for the user, they are not saved.
MacBookPro2,2, Mac OS X (10.6.3)