Microsoft has once again run into trouble with antitrust laws - this time the Russian! 

As per the Reuters Thursday report, the Federal Antimonopoly Service (FAS) of the Russian Federation has initiated legal action against Microsoft for restricting retail and OEM - original equipment manufacturers - sales of Windows XP, despite the existent demand; thereby pushing the sale of Windows Vista instead.

The Russian regulators' allegation that Microsoft has mostly stopped selling Windows XP for use on new computers varies greatly from the cases, brought by the European Commission as well as by US regulators, which are largely about bundling of products.

With the foundation of the case resting on Microsoft's violation of Russian antitrust law, for the suspected stopping of Windows XP supply in the country, the regulators have already taken the requisite action, and the case is scheduled for hearing on July 24. Furthermore, regulators apparently have adequate evidence pertaining to Microsoft's decision of providing some Vista buyers with the option to downgrade to XP.

Elaborating on its allegations against Microsoft, FAS Russia said: "According to the information given by Microsoft Russia Ltd., operation systems of the same version have different prices - OS distributed through PC manufacturers (OEM). This contains elements of antimonopoly violations, in terms of economically, technologically and otherwise unjustified fixing of different prices for the same goods."