Ashton Kutcher was on "Kimmel" the other night, and called out Charlie Sheen for bugging him about "Two and a Half Men," three years after he got fired from the show.  So yesterday Charlie apologized on Twitter, and then THREATENED Ashton with serious bodily harm if he ever did that again.  

Here's the video where Ashton talks about Charlie (fast-forward in to 3:00 to hear him talk about it).

Here's the tweet Charlie sent out after the show aired.