Winnie, the Mandela film starring Jennifer Hudson and Terrence Howard, has undergone significant changes prior to its release.

After premiering to lukewarm reviews at the Toronto Film Festival in 2010, the Winnie Madikizela-Mandela biopic has thus far failed to make it into cinemas.

Andre Pieterse, of the Ma-Afrika Films production company, and US producer Michael Mosca, say the film has now undergone several changes.

Some of these changes have been highlighted in a new trailer for the film, released 18 months after the first trailer was panned by critics and movie fans alike.

The new trailer is unusually long for a Hollywood release at five minutes and four seconds, and now has a different soundtrack and different scenes.

But both Howard (Nelson Mandela) and Hudson (Winnie) are still unconvincing when it comes to accents. Howard especially fails to capture the former president's demeanour and tone when speaking to the masses.

The film features a soundtrack written by Diane Warren which makes the love story stereotypical.

Last month, director Darrell Roodt told The Times: "It's a good film. Is it the one I made? No, but it is still a great film and I think people should see it."

The project now has the backing of Bishop TD Jakes, leader of the non-denominational mega-church The Potter's House, who has taken over as executive director of the film in an attempt to build interest in it.