You can also remove Group Policy's ability to actually apply that setting by setting up the permissions without System. Mark Russinovich has a good article on doing this.
http://blogs.technet.com/b/markrussinovich/archive/2005/04/30/circumventing-group-policy-settings.aspx
This is slightly better than a Scheduled Task to change the registry value. I wouldn't call it elegant, though :)
But really, the right way to do this is to either unset the Group Policy (as Chris Thorpe said), or disable inheritance for the server's OU and make another GPO without that particular policy.
EDIT: You can also use WMI filtering to exclude that particular server from receiving the entire policy. Note that if a particular GPO is filtered out, the ENTIRE GPO's policies are not applied. If you go this route, I'd recommend breaking out the Terminal Server connection policy into a new GPO, so the rest of the settings aren't ignored.
Microsoft TechNet info: http://technet.microsoft.com/en-us/library/cc779036(WS.10).aspx
Filtering based on computer name (scroll down for the answer):
http://www.experts-exchange.com/Software/Server_Software/File_Servers/Active_Directory/Q_22864893.html