Today Microsoft launched a last-ditch attempt to stave off the threat of million-dollar-a-day fines. The firm submitted its formal response to EC (European Commission) charges that it is failing to comply with an antitrust ruling.

In a statement accompanying the submission, the company said it had fully complied with the EC's demands to ensure interoperability with its server software and accused the EC of disregarding "critical evidence" in the case.

Microsoft submitted its formal response, a 75-page document, to the EC's complaints, known as an SO (statement of objections). In a statement, the company said: "Hundreds of Microsoft employees and contractors have worked for more than 30,000 hours to create more than 12,000 pages of detailed technical documents that are available for licensing today."

It added that it had also filed two reports by software system engineering professors who examined the technical documentation. Those experts concluded that the interoperability information provided by Microsoft met "current industry standards" and that the company had provided "complete and accurate information", according to the statement.

The EC, the EU's (European Union's) antitrust authority, did not immediately issue a comment on Microsoft's response. It had given Microsoft until today to make a convincing case that it was complying with the 2004 ruling, which among other things ordered the company to ensure the interoperability of its server software with competitors. Based on information sent by the company last December, an independent trustee, computer professor Neil Barrett, said the documentation Microsoft had provided was "useless".

The company's offer to grant access to the source code for the communications protocols for the server software has also received a lukewarm response from the EC, which argues that it does not help rivals develop products that can interoperate with Microsoft's.

Microsoft faces daily fines of up to €2m (about £1.37m) if the EC decides it has not complied with its ruling, although the actual figure would most likely be less than half that.

In its filing to the EC, Microsoft also complained that the authority had failed to consider key information it had submitted and had "denied Microsoft due process in defending itself".

The software giant said the EC waited "many months" before informing the company that changes were necessary to the technical documentation. The company was only given a few weeks to make "extensive revisions", the statement said. It also added that, when the EC issued its formal statement of objections on 21 December, it had not read the most recent version of the documents, which Microsoft sent on 15 December.

The EC will decide in the third quarter if Microsoft's response proves it is complying, since the company requested formal hearings to present its arguments. The EC needs time to consider the formal response and hearings, which are expected to take place in four to six weeks, and discuss its findings with a committee of EU member states' competition experts.

Open-source software developers dismissed Microsoft's move, calling it "a parody of compliance". A statement by Carlo Piana, a lawyer who represents the Free Software Foundation Europe and Samba Team, read: "Microsoft is not complying. It is offering pointless documents that will only have the effect of further tying competitors' hand with futile, unreasonable and discriminatory conditions."

Piana also dismissed the company's offer to grant access to the source code. The company was only allowing developers to see the code as a reference, without licensing it, he noted. "Free software is going to stay miles away from it," he said.

Companies that support the EC's case said they hoped that Microsoft had finally decided to comply with the ruling. Simon Awde, chairman of ECIS (the European Committee for Interoperable Systems), said making full server interoperability information available on fair terms for proprietary software developers and the open-source community "is the only way to ensure full and fair competition in the European server software market". ECIS represents companies including IBM, Oracle, Red Hat and Sun Microsystems.

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