Using the AJAX client revealed many fundamental ways Zimbra makes e-mail and collaboration faster -- and more seamless. Sure, there’s the familiar folder structure for organizing e-mail. But, as with any e-mail client, it takes time to compartmentalize messages -- and there’s no guarantee you’ll be able to find items later. For this reason, I really liked Zimbra’s rich search, which allowed me to find messages according to almost any criteria. Moreover, I saved these searches -- essentially giving me virtual folders to manage hundreds of views. If enabled, searches can also cross mailboxes, helpful for both basic research and compliance auditing.

ZCS 3.0 includes intelligent right-clicking throughout, another significant productivity benefit. When I right-clicked on an e-mail address, for example, the system did a quick search of all messages from that person.

An unusual collaboration feature allowed me to publish my mailbox content as RSS and Atom feeds; I can see these subscriptions helping co-workers keep informed of project changes with little effort.

The basic parts of the Zimbra client also worked well. For instance, rich text formatting made quick work of composing e-mails. The in-built viewer displayed hundreds of attachment types as HTML, so there’s no need for the originating application. Furthermore, the iCal-based calendar provided all the functions I could think of.

For organizations needing to retain Outlook clients, ZCS Connector for Outlook 2003 is a good solution. It performed mail, calendar, and contact list synchronization -- and worked in offline mode -- without any issues.

On the back end, IT staff will find that ZCS offers similar efficiencies. This starts with storage management; Zimbra saves one copy of attachments, which are then shared. The server also has advanced caching, which can accelerate message retrieval from the server.

Maintaining the system shouldn’t task admins. From the Web console, I performed full backups with Zimbra online. A great feature restores individual mailboxes, while keeping all other mailboxes accessible.

To help with uptime, ZCS comes bundled with SpamAssassin and ClamAV protection. Furthermore, you can enforce various checks, including attachment blocking; stop messages of a certain size; and validate senders IP addresses or domains. There’s native integration with Red Hat Cluster Suite.

Besides the included Zimlets, there’s a design framework for building interactive client- or server-side actions. I built a Zimlet, for instance, that recognized customer numbers in an e-mail and reached out for details in a Salesforce.com database.

ZCS 3.0 doesn’t just mimic existing e-mail and calendar systems, it injects ways to improve them. In addition to being compatible with existing e-mail infrastructures, Zimbra excels in search and Web-services integration.

Overall, both Scalix and Zimbra are technically strong and production-proven. But step back and you’ll see different personalities. The innovation award goes to ZCS 3.0 for integration with other systems through Zimlets. The company also inspires others to rethink how e-mail search can be improved.

Scalix 10 impressed me with stellar Outlook and Evolution connectors along with how far its taken AJAX Web development. The company also seems to understand the infrastructure needs of enterprises, including coexisting with existing mail systems. For these reasons I give the slight advantage Scalix.