Hi! I hope it's not too late for this response!
You can see how a bosh connection could be established doing the following:
go to http://messenger.tigase.org/, using Firefox with firebug installed.
Check firebug's console.
There you'll see all the communication interchange between an XMPPP server and a client, using BOSH.
I know this is not openfire, but I believe it should work the same. Please someone correct me if I am wrong.