As if Microsoft didn't have enough problems of its own with getting Vista out - now Symantec is looking for an injunction:

Symantec has asked a U.S. court to order a halt to the development of Windows Vista, claiming that its rival is wrongfully incorporating Veritas storage technology into its next-generation OS.

Symantec sued Microsoft yesterday, seeking unspecified damages and also asking the court to remove Symantec's storage technology from a variety of Microsoft products, including Windows XP, Windows Server 2003, and the upcoming Vista and "Longhorn" Windows Server products.

This sort of thing makes the far fetched scenario here sound possible :/