Microsoft has reached a deal with archrival Sun Microsystems in a desperate bid to unseat internet search giant Google from its high perch.

Under the agreement, Microsoft will bundle its MSN tool bar with Sun Microsystems' ubiquitous Java software in the US. For Microsoft, the deal is a symbolic coup, because it partly replaces a high-profile agreement Sun struck with Google in 2005 to bundle the Google tool bar with Java.

Microsoft, which has been ruling desktop PCs for years, is now trying to grow its reach and power in the Internet market. The software major has unveiled a number of initiatives in recent times to take on the vast superiority of rival Google in the search market.

Despite all the initiatives, including offering cash-back to users who use its Live Search to buy products, Microsoft has seen its share of the search market continue to fall, while Google's share has continued to rise. Now, Microsoft is hoping to piggyback on Java's popularity. (See: Microsoft to buy internet search with Cashback to 'get Google')

The Java software, which is needed to view some websites, is on 800 million desktops worldwide - more than 9 out of 10 personal computers connected to the internet - and gets tens of millions of downloads each month, according to Sun. The companies did not disclose the financial details of the pact. Sun has had similar deals with Google Inc. and Yahoo Inc. in the past.

Internet Explorer users who download Java for the first time or who update existing versions of the software will be given the option to also get the MSN tool bar, which includes a field for Live Search. Users who choose to download the tool bar also will be asked whether they want to switch their default search engine to Live Search.

Brad Goldberg, general manager of Microsoft's Search Business Group, said the deal with Sun was part of the company's strategy to increase the distribution of Live Search. He noted that Microsoft had also reached a deal with Hewlett-Packard to put a Microsoft tool bar on all of its new computers. That deal goes into effect in January. Under another agreement, a Microsoft tool bar is also preloaded on new Lenovo computers.

"This is the beginning of the execution of a new strategy for us," he said. "Building out distribution is one of the key things we are focused on."

''This agreement with Sun Microsystems is another important milestone in our strategy to secure broad-scale distribution for our search offering,'' said Microsoft Online Audience Business vice-president Yusuf Mehdi.

''With the vast array of Java software-based Web applications that are downloaded every month, this deal will expose Live Search to millions more Internet users and drive increased volume for our search advertisers,'' he added.

The agreement between Sun and Microsoft shows once again how far the two companies' relationship has evolved.

In 1997, Sun sued Microsoft, alleging that the company had misused its Java technology. In 2001, Microsoft settled the case for $20 million. A year later, Sun filed a private antitrust lawsuit against Microsoft, again over Java. That case was settled for roughly $1.95 billion in 2004, when Sun and Microsoft entered a broad cooperation agreement, which was expanded three years later.

Even Eric Klein, the vice president for Java marketing at Sun, commented on the changed dynamics of the relationship between Microsoft and Sun. "The nature of the basic relationship between Sun and Microsoft has changed significantly over the past couple of years," he said. "This is another rendition of that."