The company set up by MP3.com founder Michael Robertson to develop a Linux-based operating system (OS) capable of running Windows applications was in court last week after Microsoft filed a lawsuit claiming trademark infringement.

The Redmond giant is maintaining that the rival firm's LindowsOS will cause consumer confusion with Microsoft's Windows brand.

Like similar projects such as Wine, Lindows allows unmodified Windows binaries to run under Linux by translating the Application Programming Interfaces used by Windows into a language Linux will understand.

But Microsoft filed a complaint against Lindows on Christmas Eve and requested a preliminary injunction last Friday.

Details of the outcome of the hearing have not yet been released, but in a letter to Microsoft chairman Bill Gates, Robertson wrote: "As you can see, the distinct labelling and the differences of our products compel the conclusion that there will be no consumer confusion. We can also create different labelling if necessary or appropriate."

Lindows is not yet selling as a product but a 'sneak preview' version is due for release in the next few weeks.

Robertson continued: "As you also are undoubtedly aware, when our OS is ready for distribution, we plan on selling our Linux-based OS over the internet to very sophisticated and discriminating customers who would not be confused that our product was created or sponsored by Microsoft.

"In contrast, you are selling about 90 per cent of your OS to sophisticated original equipment manufacturer purchasers, while about 10 per cent are sold as CDs on store shelves."

However, Robertson also noted that he was "glad to read" in Microsoft's court filing that the company is not trying to stop or prevent Lindows from launching its OS. "They just want us to stop using the mark or slogan LindowsOS," he said.