Got another one for ya.
The paladin warhorse is treated as a henchmen until that time when you want to ride it. Then it becomes part of you and is no longer considered a henchmen.
If you have your Ox in your party and you summon your warhorse you will get the yellow script "you may only have one henchmen at a time" message. You cannot converse with it and it will ignore you. It will stay wherever you tried to talk to it, and logging out does no good, so not sure if other players see it or not.
If you want to ride your warhorse you have to tie your Ox down, thereby removing it from your party, and summon Another paladin warhorse to ride as the first one still wont talk to you.
Then, once your on your warhorse you may "lead your Ox" and all will be well.
I learned this last night after leaving 2 warhorses in fort hempstead.
I did overhear one person see me as riding an invisible horse but she was in IC chat with several other characters and they told her to ignore it so not sure if I was riding an Ghost horse or not. (other players didnt see the horse but i did)?
well..I hope i helped anyone else out there.