serverFrame.setServerURL()

s.setServerURL("myserver.mydomain.com/cgi-bin/mapserv")
Sets the address of the server to submit requests to. All variables in the serverFrame will be sent as POSTed CGI variables when the serverFrame is submitted.

At the moment the server addresses has to be the same as where the MapClient application comes from; it can come from servers with the same domain suffix if the "domain" variable has been set (see Reference Guide, globals/domain). This security issue is covered in the User's Guide 5.4.