Hello James,
I see. Ok, there are two basic steps that need be done.
1) Setup a different hostname like db.mycompany.com to be an alias of our server using the steps I gave previously.
2) Setup http://www.mycompany.com to point to a web server that redirects the user to your db.mycompany.com hostname with all the required FileMaker IWP query arguments in the URL.
http://(Server Hostname)/fmi/iwp/cgi?dbpath=%2Ffmi%2Fiwp%2Fcgi%3F-db=(Database name)%26-startsession&acct=guest&login=Login&-authdb .
Bests,
Carl Horton