Back in 2005, Joe Trifoglio, CIO of Zip Realty, needed a new email system for his 2,500 real estate agents spread out across 14 major metropolitan areas. His homegrown, open-source e-mail client worked well, but he needed something that would work on top of his custom built CRM system, known internally as ZAP, the Zip Agent Platform.

Prior to shopping for a new messaging system, Trifoglio's real-estate agents toggled between their e-mail and CRM app, and had to manually input a lot of information (such as appointments) between the two.

There were a variety of Web-based e-mail clients for Trifoglio to choose from, including Google and its Google Apps. But because Zip Realty built its CRM system completely from scratch and on Java and open source components, Trifoglio needed a messaging system built on similar principles. He picked the open-source, Yahoo-owned Zimbra, an e-mail, calendar and chat (instant messaging) client.

Trifoglio noted that other vendors offered the same features such as e-mail and instant messaging, "but they had little ability to integrate with our internal systems [mainly ZAP]."

After what he describes as moderate development work in late 2005 and early 2006, Trifoglio says the e-mail system now is embedded on top of his customized CRM, allowing his real estate agents to book showings with better efficiency than ever before.

For example, at the front end of Zip's website, people can book appointments with realtors to look at residential properties. That information is fed from the front end of the website into Zip's CRM system.

Typically, agents had to do a lot of the data input between the CRM app and their calendar app. Now, with Zimbra on top of ZAP, it happens more easily.

When an agent comes in, they now have a single sign-on that logs them onto both CRM and e-mail at once. With Zimbra, they can also add Zimlets -which are essentially plug-ins (such as one for easy calendaring) that get embedded on top of the application.

"They [the agents] are much happier because it's more feature rich," Trifoglio says. "The system allows end-users to use Web 2.0 features, like tagging emails and searching mail."

He says Zimbra also works well on Windows mobile phones, which will figure to be critical for the agents on the move. Currently, about 10 agents are testing the Zimbra app on their mobile, and have only given Trifoglio positive feedback.