Last Wednesday, Microsoft raised the ante yet again. The world's biggest software maker not only defied Brussels on the central issue of making servers running its Windows operating system interoperable with rival versions but challenged the authority and integrity of an independent trustee - charged with monitoring its compliance with an anti-trust ruling - it is, albeit reluctantly, co-sponsoring.

Almost two years ago, the then EU competition commissioner, Mario Monti, levied a record fine of €497m (£340m) on Microsoft for abusing its dominant position in the PC operating systems market: it had been leveraging its near monopoly on to markets for work group servers and media players.

Mr Monti demanded "remedies" - forcing Microsoft to disclose "complete and accurate" interface documents to enable rival servers to achieve full interoperability and to make available a version of Windows without a media player.

Twenty-three months later and, after court hearings, voluminous correspondence, private meetings between Neelie Kroes, Monti's successor, and Steve Ballmer, Microsoft chief executive, colossal lawyers' bills and millions of man-hours, the paramount issue of interoperability is unresolved. And, therefore, the threat of daily fines of €2m - backdated to mid-December - draws closer.

Microsoft argues that Brussels has wilfully ignored copious evidence of its compliance and, moreover, denied it due process - raising the prospect of yet another legal battle. In a 75-page assertion of its complete compliance with Mr Monti's March 2004 decision, it insisted it had gone beyond the commission's mandatory remedy and opened up (part) of the ultra-secret source code behind Windows to rivals willing to pay a - yet to be agreed - licence or royalty fee.

It attached a 49-page report from five computer science professors - British and German - wholly at odds with the findings of Professor Neil Barrett, the monitoring trustee, that the technical information Microsoft had supplied was "fundamentally flawed" and "totally unfit". But the report refused to name the academics and it transpires that at least one of them was nominated by the group to be the trustee - and rejected as he had worked for Microsoft in the past.

For Georg Greve, president of the Free Software Foundation Europe and one of the strongest of the commission's few backers, this latter response was "outrageous" in its implication that Prof Barrett was "biased". But for Mr Greve the stakes are even higher: as a spokesman for the "open source" software community, he sees the struggle between Brussels and Microsoft as a war for the soul of society and democracy itself.

"This is a conflict of approaches and models. Free software is not a single company or product, it's a fundamentally different approach to working with software and the computer industry as a whole: in upholding the freedom of competition we're asserting the values of a democratic society," he said.

Mr Greve, who accuses Microsoft of constantly trying to "wriggle out of its obligations", added: "They should comply and stop ignoring the commission and pretending they are above the law, because they are not. What's in it for them is money, control, power - the ability to leverage their monopoly on the desktop into new markets such as mobiles and set-top boxes."

The "open source" community is built around the Linux operating system, which, Mr Greve says, is increasingly popular with companies such as Sun, Hewlett-Packard, Intel and IBM as well as with governments. South Korea has recently announced plans to set up a university dedicated to developing Linux programmes.

But Mr Greve says: "Destroying Microsoft is not our objective at all. I believe they will learn eventually if they are forced to learn. As long as they put themselves above justice, politics and regulation, they have to be pinned to the ground ... When companies have desktops running on Windows, they have no choice but to use Microsoft servers. But if they choose to buy a new Linux server, they can help clients ... choose different desktop systems."

“While this particular worm is not fully functional, the source code could be easily modified by a future attacker to do damage,” said Vincent Weafer, senior director at Symantec Security Response. “Macintosh users should be diligent about installing patches to their operating systems as this will prevent attacks of this type.”

Inqtana attempts to use Bluetooth connections to spread itself by searching for other Bluetooth-enabled devices that will accept requests when the computer is restarted, said security experts. If a Bluetooth connection is found, the worm attempts to send itself to those remote computers.

But security experts believe that it may not be able to spread successfully, and damage from the worm could be extremely low.

The “Inqtana” worm comes a day after the discovery of a previous virus named “Leap A” or “Oompa” that spreads through the iChat instant messaging systems on Apple’s Mac computers by forwarding itself as a file to contacts on the infected user’s buddy list (see Virus Attacks Mac OS X Users). If the malicious file is clicked on and unzipped, the virus tries to spread to other contacts on the user’s buddy list. Oompa was the first worm to target the Mac OS X operating system.

Symantec has said that it does not believe the latest worm has been developed in response to the Oompa worm found on Thursday.

“We have speculated that attackers would turn their attention to other platforms, and two back-to-back examples of malicious code targeting Macintosh OS X this week illustrate this emerging trend,” said Mr. Weafer.

Bigger Target

Other security experts have said that the discovery of the viruses show that Apple Mac computers will become a bigger target in the future. According to a web poll of more than 600 users conducted by Sophos, a London-based security firm, 79 percent of respondents believed that Apple Macs will be targeted more in the future. However, more than half of those polled said they did not believe the problem would be as great as for Windows.

“The bad news is that most people think the situation is going to get worse for Macintosh users, and more threats will be targeted against the Apple community,” said Graham Cluley, senior technology consultant for Sophos.

Other security experts have said that as Apple introduces its Intel-chip-based Macs, there will be greater adoption of the operating system, which could trigger malware writers into creating more threats for the Mac.