Well, as long as there is no firewall between the Cassini and the outside world (or your IT), those parties will be able to figure out that there is a listener on a port, even if the listener immediately rejects incoming connections based on some criteria. Even WebDev.WebServer.exe, which responds to requests from the localhost only, still would be detected as a listener by the outside world. The code snipped in the forum post does for your app what WebDev.WebServer and original MS Cassini sample did.
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UltiDev Team.
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