The Electronic Frontier Foundation has published an open later urging Sony to consider a product recall of CDs shipped with the controversial XCP copyright protection software that secretly installs a cloaking utility on computers.

The move is the latest in what has developed over the week regarding Sony's move to include anti-piracy technology that prevents Windows users from making copies or loading the CD's songs onto an Apple iPod digital music player.

Last week Microsoft announced that it was regarding the software as spyware following the news that hackers had exploiting the ability of the anti-piracy technology to avoid detection and has since offered users tools to remove it.

After nearly 2 weeks of consumer backlash, however, Sony announced on Friday that it would temporarily suspend production of XCP-enabled CDs.

In the letter addressed to Andrew Lack, CEO of Sony-BMG, Rolf Schmidt-Holtz, Chairman of the Board, Sony-BMG, Howard Stringer, CEO of Sony Entertainment, and Gunter Thielen, CEO of Bertelsmann AG the Electronic Frontier Foundation argues that:

“It was written with the intent of concealing its presence and operation from the owner of the computer, and once installed, elements of the software run continuously - even when no Sony-BMG music CD is in use. It provides no clear uninstallation option. Additionally, without notifying users, the software appears to contact a remote machine under your control”.

The letter goes on to say:

“You must be aware that the discovery of this software has shocked and angered your customers. Software that deceives the owner of the computer it runs upon and opens that computer up to attacks by third parties may be expected to come from malicious cyber-attacks; it is certainly not expected nor acceptable to be distributed and sold to paying customers by a major music company".

The letter finally praises Sony for halting production by insists that users must be informed of what the software is capable of in the future:

“Accordingly, EFF welcomes your company's decision to temporarily halt manufacturing CDs with XCP and to reexamine 'all aspects' of your 'content protection initiative'".

The full letter can be read at