Let's say I have 20 remote users all of whom get a Dynamic IP. I have found that getting the user to find their IP address is a pain in the A... Some of my users get a new IP several times a day. Others keep it for days.
So my best case idea would be to have all the users I support linked to my viewer and when their IP changes I automaically get the right IP address.
Another suggestion to fix your original issue (without having to wait for Server 3.0) is to use either NetBIOS or DNS names, depending on your network setup, rather than IP addresses. That way the same mechanism that updates the name mapping will also keep RAdmin connecting.
How about just use DNS instead of IP?
My home external IP started changing frequently (grrr.... Comcast) so I registered with http://www.dyndns.com. They have a free service that will assign DNS name to your IP (you can choose a name).
So, now I just put in my DNS name into the client configuration window instead of IP and can connect any time.
I always use the DNS name of client PC's. I don't ever use IP address unless absolutely necessary (connecting over WAN without VPN tunnel).
But getting your users to know their IP address is very simple. Just point the mouse at the little R down in their system try by the clock. Viola! A popup box shows their IP address. Call me wacky, but that seems pretty simple to me...
Basco Shower Enclosures