Adobe Systems Inc. (ADBE) said on Wednesday Google Inc. (GOOG) had agreed to pay the multimedia software maker a "significant" amount to distribute Google's Web search software over several years.

In a statement, Adobe said it had begun distributing Google search software with new downloads of Adobe's Macromedia Shockwave multimedia playback software, which allows users to view interactive Web programming such as games, entertainment, business presentations, and s via a Web browser.

This and similar recent deals to pre-install Google software marks a change of course for the icon of Web search, which historically has incurred little upfront cost to attract customers to its services. Instead, it has shared a portion of advertising revenue with partners who drive traffic its way.

The deal calls for users to receive Google Toolbar Web search software each time they download Adobe's Shockwave player for use with an Internet Explorer browser.

Google is racing to do deals with software and computer makers to ensure convenient access to its search software ahead of the arrival of Vista, the new version of the Windows operating system, due out over the course of the coming year.

Vista is preparing to offer Microsoft's (MSFT) own search system as a default setting in Vista, potentially undermining Google's dominance of the consumer Web search market.

"The popularity and reach of Adobe technology gives Google even broader exposure to a growing base of consumers," Shantanu Narayen, Adobe's president and chief operating officer, said in a statement.

The Shockwave player has been downloaded 200 million times and runs on an estimated 55 percent of Internet-ready desktop computers, Adobe said.

"We expect the agreement to represent significant revenue to Adobe over a period of years," Narayen said.

Last month, Google struck a "toolbar" partnership with top computer maker Dell Inc. (DELL), which analysts have speculated involves big upfront payments to win prominent placement for Google's Web search and other services on Dell PCs. Google has declined to comment on the payment structure.