Gwyneth Paltrow has cast doubt over her Two Lovers co-star Joaquin Phoenix's new 'music career' admitting she suspects it's a hoax.

The Gladiator star recently revealed he had quit acting to become a rapper.

He has since made a string of bizarre public appearances, including two nightclub performances, the last of which ended with an angry confrontation with a heckler, in Miami, Florida on Wednesday.

Skeptics have suggested Phoenix's hip hop endeavors are being staged as part of a prank project - and Paltrow admits she's not convinced by his claims.

The actress tells MTV, "I'm not a hundred percent sure that that's really going to be the case. I think that there might be some other explanation or something going on. I'm not quite sure what, but I can't believe that he's really going to quit forever to become a rapper. It seems odd."

(This news article provided by World Entertainment News Network)