Their most recent meeting was in the 2009 Champions League semi-final between Arsenal and Manchester United. Di Canio, 50, was working as a commentator for Italian television and was in the car park congratulating Michael Carrick after the game.
"I remember that Ferguson saw me and he went out from the coach and shouted `Paolo Paolo' and he came to me and said `how are you?" Di Canio said.
"It was another incredible moment for me. He meets thousand people and to say how are you that gave me another dimension of the man and values of him as a person and his respect for people."