Google escalated its antitrust battle with Microsoft Monday by questioning its rival's promised changes to Windows Vista search and asking a federal judge to extend oversight to make sure Microsoft follows through.

In a seven-page brief, Google is asking for permission to file with a federal court in Washington, Google staked out the same position it voiced last week. "Microsoft's hardwiring of its own desktop search product into Windows Vista violates the final judgment in this case," the brief read.

Microsoft responded by saying there's nothing new to Google's latest maneuver. "We believe we went the extra mile to resolve these issues in a spirit of compromise," said company spokesman Jack Evans. "The government has clearly stated that it is satisfied with the changes we're making. Google has provided no new information that should suggest otherwise in their filing."

Less than a week ago, Microsoft agreed to make modifications to Vista's handling of desktop search. On Monday, however, Google again said that the changes weren't sufficient. "The remedies won by the Department of Justice and state Attorneys General from Microsoft are a positive step, but consumers will likely need further measures to ensure meaningful choice," said David Drummond, Google's chief legal officer. "Ultimately, these issues raise the need for continued judicial oversight of Microsoft's practices to ensure that consumers' interests are best served."

Among several objections listed in the brief, Google said Vista would continue to call on Instant Search when users run searches from locales like Windows Explorer and that users will still not be able to easily disable Microsoft's desktop search.

And while the deal struck last week would have Microsoft allow users to select a default search tool in Vista, then use that tool for searches done from the operating system's Start menu, Google hinted that Microsoft may cut off its nose to spite its -- or its rival's -- face. "Google understands that Microsoft may intend to remove these [Search] menu entries from Vista and deprive users of these access points altogether rather than provide the user choice required under III.H.1(a) of the Final Judgment," Google charged.

To better monitor Microsoft's promises, Google suggested to federal district court Judge Colleen Kollar-Kotelly, who oversees the 2002 antitrust decree, that she extend her oversight. Sections of the settlement, including the part that would conceivably pertain to search, are to expire Nov. 12 2007, but government regulators can unilaterally ask to extend that deadline by two years or even an additional three after that to November 2012.

In any case, Google's brief may be moot; Kollar-Kotelly has a history of rejecting outsiders' efforts to join the case. In a November 2002 opinion, for instance, she wrote: "While there is no inherent flaw in giving third parties a voice in this process, as very often such third parties will be most immediately aware of Microsoft's conduct, non-parties should not be allowed direct access to the enforcement mechanisms."

Chris Wolf, an attorney who chairs the Internet law practice of Proskauer Rose in Washington, said he sees no chance that the judge will start now. "There's no reason why she would change her practice of the past, especially with a brief filed by one who is so obviously a competitor of Microsoft and thus has an ax to grind.

"It would be very different if one of the plaintiffs made these arguments," Wolf said. "But Google's certainly not bashful. It could have done this earlier and likely did, but it was rejected."

"This would be unprecedented," added Microsoft's Evans. "This would be the first time that an operating system would require a third-party product for underlying functionality."

Google filed the "friend of the court" brief a day before Kollar-Kotelly is to hear a status update. That hearing is scheduled to begin at 10:30 EDT Tuesday.