Masking the URI and also redirecting!

How about this?

when HTTP_REQUEST { 
   if { [HTTP::uri] equals "/" } { 
     HTTP::uri "/home" 
   } 
 }

I think this satisfies all your criteria.

1. for http://www.site.com/, URI is converted from "/" to "/home" and sent to the backend server. The browser doesn't need a redirect for this and the address bar stays the same (http://www.site.com)

2. There will never be a request of (http://www.site.com), as hoolio mentioned, the browser will append a slash to empty URIs, so the URI will always be at a minimum a slash.

3. All other URI's are left alone and sent as is to the backend servers.

-Joe