doubletwist.bmpHacker Jon Lech Johansen, who became known for cracking the copy-protection technology in DVDs, now claims to have unlocked the playback restrictions of Apple iPod and iTunes music products and plans to license his code to others. There’s a summary of his plans by the Associated Press.

He says he is on solid legal ground.

Today, songs purchased from Apple’s online iTunes Music Store can’t be played on portable devices made by other companies. Songs purchased from many other online music stores also won’t work on iPods because they similarly use a form of copy-protection that Apple doesn’t support.

Johansen said he has developed a way to get around those restrictions by creating code that mimics Apple’s copy-protection system. But unlike his previous work, which he usually posts for free, the Norway native plans to capitalize on his efforts through his Redwood Shores-based DoubleTwist Ventures, said the company’s only other employee, managing director Monique Farantzos.