FOR IMMEDIATE RELEASE

Zimbra Expands Support for Award-Winning Collaboration Suite

Suite now offers Safari 3 integration, CalDAV support for iCal on Mac OS X Leopard, and optimized iPhone support

SAN MATEO, Calif. - January 15, 2007 - Zimbra, a Yahoo! (Nasdaq: YHOO) company, and the leader in open source, next-generation messaging and collaboration software, today announced that it has expanded its support for Apple products and technologies, including Safari 3 and CalDAV for Mac OS X Leopard.

"The amazing speed of Safari 3 has blown the Zimbra team away and we are excited to be the first major collaboration platform to support the calendaring standard CalDAV," said Satish Dharmaraj, CEO and co-founder of Zimbra. "We also wanted to expand our support for the iPhone by adding an optimized mobile web experience on top of our iSync support."

"Leopard is packed with more than 300 new features, including major enhancements to Safari and iCal," said Ron Okamoto, Apple's vice president of Worldwide Developer Relations. "We're pleased that Zimbra users can take advantage of the world's fastest browser with Safari and improved iCal group calendaring with CalDAV in Leopard."

The Zimbra Collaboration Suite (ZCS) fully supports Safari 3, which is the fastest Web browser on any platform and is available for Tiger and Leopard users and is in beta on Windows. ZCS's rich AJAX interface, including email, calendaring, Zimbra Documents, and customizable mash- ups called Zimlets, takes full advantage of Safari's optimized AJAX browsing experience.

To meet the advanced calendaring needs of Mac users, Zimbra now supports CalDAV, a key feature for customers using Leopard's iCal 3 as their calendaring client. Based on a public standard, CalDAV allows users to synchronize and browse free/busy time and recurring appointments easily, both with personal and public calendars.

Additionally, ZCS is now available to iPhone users via the Zimbra Mobile HTML client. The iPhone's Safari browser enables fast access to the full-featured AJAX interface, and the Zimbra Connector for Apple iSync allows users to sync not only their email but also their address books and calendars to their iPhones.

These enhancements reflect Zimbra's ongoing commitment to the Mac community, and to providing innovative features for the Mac platform. Zimbra has long supported iSync, which provides a two-way sync between Apple Mail, Address Book, iCal, Microsoft Entourage, and the ZCS server. To test these new capabilities including support for Safari, CalDAV and iPhone, visit http://www.zimbra.com/ and register for a Hosted Demo Account.

Pricing and Availability

The ZCS 5.0 Open Source Edition, available now, is free. The commercially supported ZCS 5.0 Network Edition is available for a 60-day free trial on the Zimbra Website. ZCS Network Edition is available at a significant educational discount by contacting sales@zimbra.com. The Network Edition includes product support as well as software subscriptions to new releases, updates and patches. ZCS is available on-premises or as a hosted service; for information about Zimbra On-Demand or Zimbra's hosting partner program, please visit http://www.zimbra.com/partners/. Users can discuss topics related to the Zimbra Collaboration Suite and provide feedback at http://www.zimbra.com/forums/.

About Zimbra

Zimbra, a Yahoo! company, is a leading provider of collaboration software for universities, businesses and service providers. Zimbra's rich AJAX interface is available on or offline to dramatically improve the collaboration experience. Zimbra is available on-premises or on-demand through our extensive hosted partner program. More information at http://www.zimbra.com/.

About Yahoo!

Yahoo! Inc. is a leading global Internet brand and one of the most trafficked Internet destinations worldwide. Yahoo! is focused on powering its communities of users, advertisers, publishers, and developers by creating indispensable experiences built on trust. Yahoo! is headquartered in Sunnyvale, California. For more information, visit pressroom.yahoo.com or the company's blog, Yodel Anecdotal.

Media Contact:
Liz Clinkenbeard
OutCast Communications
(415) 392-8282
liz@outcastpr.com