No, you don't need to install AOLserver again but you do need another nsd.tcl. You also need another database user and another copy of all the tcl and adp files. A (very) rough outline of a quick and dirty solution is to take an export dump of your current database, create a new database user and then import the dump to the new user. Then copy your tcl and adp files to another directory. Then make a copy of your nsd.tcl, edit it and change the port, database user and serverroot and off you go. (You might need to copy your aol/servers/yourserver directory too.)
