Did you ask him about a treasure map?
He asks for a longtooth hide in exchange for the map to his treasure which, coincidentally, is right next to the Sunken City...leaving you without having to search the whole Lost Sea for it.
Did you obtain a quest (From the Pawn Shop I think) to deliver to him a hook?
If you are playing with multiple characters who are eligible to obtain this quest, remember that there is limited room in his inventory and you may have to steal some back before you can give him more.
Moni