A long-simmering dispute over technology used in Microsoft's Xbox 360 game console has heated up. Defendant Microsoft, sued by Lucent Technologies in March for infringing on patents it owns, has filed a countersuit denying the Lucent claims and brings a few charges of its own.

　　In documents filed Monday in a US District Court in San Diego, not only did the console maker deny infringing on a 1993 Lucent patent which concerns MPEG-2 video encoding (Patent No. 5,227,878, titled "Adaptive Coding and Decoding of Frames and Fields of Video"), it argued that the initial claim of Lucent is invalid, reportedly due to Lucent's failure to disclose prior art when making its initial application with the US Patent and Trade Office.

　　Monday's counterclaim also accuses Lucent of infringing on a number of Microsoft-owned patents.

　　In an e-mail statement published in The Wall Street Journal, a Microsoft attorney on the case said, "Microsoft stands behind our intellectual property, our customers and our partners." He also took a stab at characterizing Lucent as reluctant to reach a resolution in the dispute. "Rather than engage in meaningful licensing negotiations," the lawyer said, "Lucent continues to choose to litigate against Microsoft and our customers."

　　While lawyers for the two camps draw sabers in court, there seems to be little fallout on the Xbox 360 agenda at large. Reportedly, Lucent has requested a jury trial and monetary damages from Microsoft, but has yet to seek any sort of injunction to prevent Microsoft from continuing to sell the "infringing" console.