Good catch. It's funny,as many times as I've watched that scene,I never really listened to the voice. I assumed that it was Tessio because he handed Sonny the package. They don't show anyone's face while the line is delivered.
I swear up until now,I would have bet that it was Tessio. That's why I love this board.As many times as I've seen the movies and the Epic,there's still stuff I learn from the posters here.