Apple's latest iTunes update, which takes the jukebox software to version 4.7.1, breaks the anti-DRM utility Hymn, it has emerged.

The move marks the latest step in the Mac maker's attempts to prevent users stripping away the limitations it imposes on music downloaded from its iTunes Music Store.

Using applications like Hymn is, of course, contrary to Apple's ITMS terms and conditions. In the US and Europe, using the software is also an infringement of laws that forbid the circumvention of copy-protection mechanisms.

Hymn advocates, however, argue that the code simply re-establishes usage modes to which they have become accustomed, such as converting files to MP3 in order to play them on non-Apple portable music players. They stress that the code is not intended to facilitate unauthorised distribution of iTunes-sourced content, although the software does make this possible. But then so does ripping tracks from any standard CD.

Hymn strips away the DRM rights management data, space for which is incorporated into the AAC audio format Apple uses for ITMS. Apple also uses other elements within the file structure to identify protected AAC tracks, and one or more of these seems to have been added to iTunes 4.7.1's list of checks.

Apple appears to use the same procedure to spot files converted by Real Networks' Harmony software, which transplants Real's Helix DRM code for Apple's FairPlay DRM information. Like ITMS, Real's Rhapsody online music uses AAC as its file format.

Hymn users may be annoyed with the breakage, and the hoops they may now have to jump through to get tracks playing again. but Apple's has solde 230m songs to date and is selling 1.25m on averager each week; this shows that plenty of people are willing to work with Apple's - fairly liberal, as these things go -DRM limitations.

Real has pledged to get Harmony working again, so Rhapsody customers can once again copy and play their downloads on iPods. Hymn's developers say they too will tweak their code. Expect Apple to do so too. The game of cat and mouse continues. ®

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