Hi! I hope it's not too late for this response!
You can see how a bosh connection could be established doing the following:
1. go to http://messenger.tigase.org/, using Firefox with firebug installed.
2. log in.
3. 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.
I spent a little bit of time attempting to make it work and did not have any luck. My best guess was that the versions of BOSH expected were not compatible.