Apr 29, 2009, 4:00 GMT
Joaquin Phoenix is "dedicated" to his rap career, according to Charlatans frontman Tim Burgess.
The singer - who has worked with the actor on previous musical projects - insists his friend's change in direction is serious, despite claims his hip-hop career is a stunt for a spoof documentary.
He said: "Have you seen that film where he plays Johnny Cash, 'Walk The Line'? He's just like that. Actually, he is really dedicated to whatever cause, whether it's the music or acting. I've seen him do music then have to go off and do a film and he's more focused than anyone I've ever seen.
"With his new thing, I think historically when he was a kid he used to rap and stuff like that."
Joaquin's new career has been the subject of much speculation he is staging an elaborate hoax due to his increasingly strange behaviour - which includes throwing a tantrum after his documentary crew were late to a sound check, attacking a fan and giving a bizarre incoherent interview to David Letterman - and Tim says even he is unsure of the truth.
The rocker added to BANG Showbiz: "I have no idea what's going on right now because everyone's sworn to secrecy, even friends of his I know. I mean I've not seen him for two years, but whatever's happening is happening and I think its going the way he wants it to go."
Your Talkback on this Story