Microsoft is striking back at a growing grass-roots movement in the Bundestag (Germany's lower parliamentary house) that is seeking to switch from the current Windows operating system to Linux's open-source OS.

A parliamentary committee is due to decide by the end of this month whether to renew Microsoft licences for the Bundestag's some 5,000 PCs, or to switch to Linux.

This is another potential European blow for the bloatware behemoth after, for example, UK police said they are considering whether it could deploy Linux here.

Kurt Sibold, chairman of the board of Microsoft's German subsidiary, accused initiators of a pro-Linux petition of smearing the software company's reputation.

"What you are achieving by supporting this campaign is public discrimination, accusing our products and services of being undemocratic and an obstacle to democracy," he wrote in an open letter to signatories of the online petition, known as

The petition campaign was launched last week with 12 initial signatories, among them several members of parliament and open-source fans including (unsurprisingly) commercial Linux distributor Red Hat's managing director for central and eastern Europe, Dieter Hoffmann.

Within two days, more than 11,000 other supporters added their names, according to a statement from the petition committee.

The petition asks the Bundestag to take a stand against 'monopoly positions', pointing out that Microsoft's operating system, Internet Explorer web browser and email programs hold a market share of over 90 percent in Germany. It also appeals to government bodies to implement open-source software for 'democratic' reasons.

"The democratic component is not simply in the increased security and flexibility of the software, but is more the expression of a broad democratic understanding that encompasses economic and technological developments. Based on these considerations it is plainly the duty of a democratic state to choose free software," the document reads in part.

That was too much for Sibold, who wrote: "But what does a decision for or against an operating system have to do with 'democratic rules of the game'? Open source software is... not, per se, a guarantee for free-market competition, just as a decision to use my company's products is not at present, nor was it in the past, an 'undemocratic' decision."