That means happy birthday, so I am guessing someone said it to Vito in the flashback scene at the end of GFII

"Io sono stanco, sono imbigliato, and I wan't everyone here to know, there ain't gonna be no trouble from me..Don Corleone..Cicc' a port!"

"I stood in the courtroom like a fool."

"I am Constanza: Lord of the idiots."