Zimbra, whose software runs 2 million mailboxes on college campuses, is about to become a hosted e-mail service for education.

Zimbra under former CEO Scott Dietzen was an open source applications supplier, acquired by Yahoo a year ago for $375 million. Now Dietzen is senior VP of the Zimbra division at Yahoo and will capitalize on Yahoo's data center management ability to convert Zimbra into a supplier of e-mail as a service.

Zimbra runs 20 million mailboxes through its existing approaching of getting customers to install on-premises software. It's looking to more rapidly expand its foot in the door in education institutions, one of its strongest markets. "Education wants desktop neutrality," said John Robb, Zimbra VP of marketing. Zimbra e-mail runs on Windows, Macintoshes, and Linux systems, all of which are found in the university environment.

By offering desktop-neutral applications as a hosted service, Zimbra will make it easier for educational institutions to adopt its e-mail and other selections in its Zimbra Collaboration Suite. The suite includes a calendar, word processor, and contact manager, as well as an e-mail server that can merge mail for users from Microsoft Outlook, Google Gmail, Yahoo Mail, and AOL.

Zimbra already provides e-mail through on-premises software at a number of marquee education accounts, including Stanford University, Georgia Tech, the University of California at Davis, Pennsylvania University, Northeastern, Carleton College, Texas A&M, and Mississippi State. It will launch its e-mail hosted service at Kansas State University and Kaplan Art Center College of Design in Fort Lauderdale, Fla.

E-mail will be offered as a hosted service in a free, advertising-supported option, or as a paid-for service that gives institutions the chance to brand it with their university emblems and design colors, Robb said.

Zimbra combines online service with offline ability to continue to read e-mail and prepare messages on the mobile Zimbra Desktop for sending upon renewal of the network connection. Faculty mail may be engineered around service to a variety of clients, including BlackBerrys. Mobile access can be granted to students or faculty from laptops, iPhones, Java Mobile Edition devices, or any mobile Web browser.

Robb said one likely user of the hosted service is alumni, who move into careers but hate to give up their college e-mail addresses, which keep them in touch with classmates. An advertising-supported alumni service allows alums to maintain their addresses and service for free. Zimbra is charging institutions $2 a year per mailbox for the branded hosted service, or free if supported by advertising. On-premises Zimbra systems managed by the school's IT staff are priced at $1.50 per mailbox.

Faculty systems contain more features and are priced at $35 a year per faculty member as a hosted service; $8 a year per member as an on-premises system.