Yahoo-who? Microsoft and Sun Microsystems are getting together to more closely ally the Java Runtime Environment and Internet Explorer's search.

Microsoft announced on Monday that the MSN Toolbar will now be included in all US Java Runtime Environment downloads for Internet Explorer. That toolbar includes Live Search access, direct connections to Hotmail and Messenger, and buttons to take users to MSN content such as sports scores.

The arrangement doesn't exactly fill the bill that a Yahoo acquisition would for Microsoft, but don't sell short the JRE's reach -- it's installed on 91 percent of Internet-connected PCs around the world. The equivalent percentage of the US market (the toolbar download will be limited to US-based users) would help Microsoft to make some noise in its ongoing struggle to lift itself out of third place in the search wars.

Sun has also made deals in the past with those other two search sites, and its current arrangement with Yahoo to offer a Firefox toolbar for users of that browser will remain in place. The Google deal, however, is off.

As for Sun, the financial arrangements have not been disclosed, but after the company's dismal financial results last quarter, the one-time Microsoft adversary may regard any Redmond deal in a favorable light.