Two of the three surviving members of the Clash -- guitarist Mick Jones and drummer Nicky "Topper" Headon -- have recorded together for the first time since sessions for 1982's 'Combat Rock.' The former bandmates have joined forces with activist musician Billy Bragg and several inmates for a rendition of their 1978 song 'Jail Guitar Doors' in an effort to promote a campaign to help rehabilitate prison inmates.

Bragg's Jail Guitar Doors program, named for the song, provides musical instruments to prisoners and has led to several of them pursuing careers as performers in the two years since the initiative began. "The guys were telling us how much this scheme had helped them move on from their previous lives before prison," Jones said in a statement. "It was really touching to think we've helped, even if it's in a small way."

For former inmate Headon, who was sacked from the Clash over his heroin addiction and served time on a 1986 drug conviction, said, "When I was in prison myself, many years ago, I was lucky enough to have access to a guitar, which belonged to the prison vicar! I know how much it helped me get through it. To see [this session] come to fruition is absolutely beautiful."

"We want people to be able to move on from their situation and reconnect with the outside world, and my hunch was that playing an instrument -- particularly a guitar -- could help that," added Bragg, who was inspired to pursue a musical career after witnessing the Clash live at a 1978 Rock Against Racism gig in London. He formed Jail Guitar Doors in 2007, citing statistics that showed recidivism rates to be much lower among inmates who attended prison guitar workshops.

Footage of the recording session will be included in a new documentary about the initiative titled 'Breaking Rocks.' The documentary will debut at the Raindance film festival at Proud Gallery in Camden on Oct. 1. Performances by Bragg, Jones, the MC5's Wayne Kramer, Chris Shiflett of the Foo Fighters and others will follow the film's premiere.

To see a video from the session, head over to the Clash Blog.