Microsoft says it's willing to put a "ballot screen" into Windows 7 to let European consumers choose from among several competing web browsers as the default in the operating system. The concession is aimed at resolving an antitrust complaint filed against the company in Europe by Opera Software over the bundling of Internet Explorer in Windows.

"European consumers who buy a new Windows PC with Internet Explorer set as their default browser would be shown a ‘ballot screen’ from which they could, if they wished, easily install competing browsers from the Web," said Microsoft general counsel Brad Smith in a statement. "If this proposal is ultimately accepted, Microsoft will ship Windows in Europe with the full functionality available in the rest of the world."

In that way, the new proposal would replace Microsoft's previous plan to offer a version of Windows 7 in Europe without Internet Explorer. Microsoft said it will soon publish the full text of the proposal online as soon as possible.

The proposal represents a possible breakthrough in the European case, which is the latest to challenge Microsoft's practice of bundling Internet Explorer with the dominant Windows operating system. Rivals contend that the practice gives Internet Explorer an unfair advantage.

The European Commission said in a news release that it welcomes the proposal and "will now investigate its practical effectiveness in terms of ensuring genuine consumer choice."

"This is a very encouraging step," said Hakon Wium Lie, chief technology officer at Oslo, Norway-based Opera Software, in a phone interview. "It's a happy day for us around here."

Although Windows 7 has been finished, in preparation for Oct. 22 release, the ballot screen could be implemented via the operating system's automatic updating feature, Lie said.

He noted that the effectiveness will depend on how the ballot screen is presented. Among other things, Opera would prefer that the ballot screen not show the logos of different browsers. Because Microsoft has bundled Internet Explorer with Windows for so long, Lie said, many consumers see the blue IE logo as a generic symbol for accessing the Internet, possibly making them more likely to choose it over the logos of rival browser vendors.

In addition to the ballot screen, Microsoft's Smith said the company's proposal "also includes a public undertaking designed to promote interoperability between third party products and a number of Microsoft products, including Windows, Windows Server, Office, Exchange, and SharePoint."

The interoperability steps would apply globally, a Microsoft spokesman said, but the browser ballot screen would be limited to copies of Windows 7 distributed in Europe.

"We believe that if ultimately accepted, this proposal will fully address the European competition law issues relating to the inclusion of Internet Explorer in Windows and interoperability with our high-volume products," Smith said. "This would mark a big step forward in addressing a decade of legal issues and would be good news for European consumers and our partners in the industry."