Hill appeared on late night TV in America last week (21Sep11) and revealed Morrison was less than kind to him at a recent Fox network party, when the singer/actor chastised him for allegedly chatting during a presentation.
The Superbad star was less than amused when he then attended another Hollywood party and overheard Morrison talking about him again - so he jokingly threatened to show Morrison exactly how he feels the next time they meet.
He said, "Yo, Matthew Morrison you better bring your s**t next time I see you dude!"
But Morrison has taken the fighting talk in his stride - and has called on Hill to name the time and place.
In a pre-recorded video sent in to TV host Jimmy Fallon on Monday (26Sep11), Morrison says, "Oh hey Jimmy, what's up? So I heard what went down on your show the other day. I heard that Jonah Hill said I should bring my s**t next time. Well guess what? This is next time. You think I can't sing my way out of it? I can sing my way out of it; I can dance my way out of it.
"So listen, Jonah, pick a date and I will meet you on Late Night with Jimmy Fallon and we will settle this like men. Be afraid, be very afraid - because no one messes with someone from musical theatre!"