In an old post (
http://forums.polserver.com/sutra8094.php#8094) Muadib quoted a changelog never seen in official
core-changes.txt: is this really implemented or not?
Quote:
-- POL096.7 --
4-19 MuadDib
Added : Core support for replying to 0xF1 custom packet used by UOGateway and ConnectUO. None of the data is prefilled, so just use an outgoing packethook to fill this information however you wish

Using an UOGateway-style monitoring site, in console I see:
Quote:
Client#nnnn (aaa.bbb.ccc.ddd, Acct unknown) sent non-allowed message type f1.
even with an 0xF1 hook enabled!
