Ashton Kutcher, Charlie Sheen beef: Mila Kunis' boyfriend tells former 'Two and a Half Men' star 'dude, shut the f*ck up' on 'Jimmy Kimmel Live' after Twitter attack [VIDEO]

Apparently, Charlie Sheen is still pretty bitter with Ashton Kutcher for taking over his lead role on the hit comedy sitcom "Two and a Half Men." As Mstars previously reported:

Hollywood rebel Charlie Sheen once said that CBS "picked the right guy" when replacing him with Ashton Kutcher on the hit comedy series "Two and a Half Men."

Apparently he's had a huge change of heart.

@charliesheen: "hey Jon!!! u r a GENIUS!!! I effin love and MISS YOU old pal! Q; who's your lame side-kik? #NiceTryCanonBoy #CH."

The "Anger Management" actor's been posting some VERY bizarre tweets lately, just check it out.

Not sure what the deal is... but Sheen's sort of pulling a major Amanda Bynes.

What's up with that?

FYI - Kutcher is a spokesperson for Nikon, not Canon.

And Kutcher's response? "Dude, shut the f*ck up!"

On Wednesday evening's episode of "Jimmy Kimmel Live" (Feb. 5), Mila Kunis' boyfriend pleads, "Seriously! Enough already! It's like three years later, and you're still blowing me up on Twitter?"

Check it out:

Oh my, wonder what Sheen will do next?