A week after the European Union's antitrust chief blasted Microsoft for continuing to make millions using tactics declared illegal in a 2004 ruling, the group has extended the deadline the company faces before new fines are assessed.

The EU's Competition Commission had originally set 3 April as the date for Microsoft to respond to charges that it has overpriced protocol documentation necessary for rivals to make their applications work smoothly with its server software. The new deadline, announced Tuesday, has been pushed back nearly three weeks, to 23 April.

Microsoft requested the additional time, said commission spokesman Jonathan Todd, and it was granted by the hearing officer handling the case.

Microsoft spokesman Jack Evans confirmed that the company asked for the extension. "We have until 23 April to submit our response and [we] intend to do so by that date," said Evans in an email.

The 2004 ruling ordered Microsoft to share several server protocols with competitors and fined Microsoft a record $613 million. Last July, the commission added another $373 million in fines, saying Microsoft was dragging its feet in preparing the documentation. Microsoft has appealed both fines to EU courts.

On 1 March, however, Commissioner Neelie Kroes said that the documentation Microsoft had assembled lacked "significant innovation" and thus the prices it charges were "unreasonable." She threatened new fines of $4 million per day if Microsoft didn't respond within 30 days.

At the time, Microsoft's general counsel, Brad Smith, complained that the EU was again changing the rules. "The proposed findings suggest that unless our intellectual property is innovative and patentable, it has to be made available royalty free," he said. "That has never been the standard for software or other intellectual property."

Last week, Kroes turned up the heat in a speech before the European Parliament, where she said it was "unacceptable" that Microsoft has continued to gain server software market share since the 2004 decision. Since then, Kroes said, the company's share in the EU has climbed from around 60 per cent to between 70 per cent and 75 per cent.

Microsoft has the right to an oral hearing before any new fines are levied.