If it helps, hereÂ´s what Wikipedia has to say about DRM removal
Tools have been created to strip files of Windows Media DRM, enabling them to be played on non-Janus platforms.
It was claimed that one particular tool FairUse4WM (Released on August 19, 2006) written by Viodentia had the ability to strip DRM from files protected with WMDRM . However, on August 28, 2006 Microsoft released a new version of the individualized blackbox component (IBX) to prevent this particular tool from working.
Microsoft also informed partners that they are working to further resolve this issue, given that the fix was also alleged to have been circumvented within days. Microsoft also issued takedown notices to web site owners. They soon followed up by filing lawsuits,  although this has been disputed by the operator of the highest-ranked mirror of the utility, James Holden, who has not received any such notices or threats.
As of October 16th, distributors using the Windows Media DRM protection, such as Sky Anytime, are up and running using a patched codec. On April 6, 2007 Microsoft dropped the charges against Viodentia as they were unable to find him to serve him with court papers.
On September 6, 2007, Microsoft updated IBX to version 11.0.6000.7000, in an attempt to thwart circumvention efforts by variants of the original program.
As of November 28, 2007, DRM Removal under Windows XP on new installs or updated computers (i.e. those that already contain IBX version 11.0.6000.7000), is now not possible without rolling back to Windows Media Player 10. Recently, a patched version of FairUse4WM was released, allowing it to work with Windows Vista, and IBX versions lower than 11.0.6000.6324.
[B]Maybe more specifically useful in your case[/B]: http://5thirtyone.com/archives/873