Register Assistant to the "qthelp" URL Protocol

On Windows and OSX (probably also on Linux), an Application can be registered as a handler for specific URL Protocols. Whenever, and from whichever application, I click a link with a registered Handler, the registered Application will launch and receive that link as parameter.

So, if Trolltech support sends me a mail with a qthelp:// link, the registered application (Assistant) would be launched when I clicked that. Isn't that fantastic?

How to do that on Windows:
http://msdn2.microsoft.com/en-us/library/aa767914.aspx

Sounds like a job for the Installer or the first launch of Assistant.