By Justin Silverton

After the recent announcement by Novell that they were dropping support for the Hula project (an open alternative to Microsoft exchange), I decided to search the Internet for similar applications/projects.

1) Zimbra (commercial and free versions available)

• Desktop client compatibility. Sync mail, contacts, and calendar to Microsoft Outlook and/or to Apple (Mail, Address Book, iCal).
• Professional administration. Real time mailbox backup and restore, high availability clustering, storage cost management.
• Zimbra Mobile. Over-the-air synchronization of mail, contacts, and calendar data with mobile devices.
• Advanced web productivity. Ability to search for content inside attachments and view attachments as HTML instead of downloading.
• Domain management. Ability to re-brand the web client and administer multiple customer domains.

2) Open Xchange (commercial and free versions available)

• Linux Compatibility.  Support 30 different linux distributions.
• All Information in One folder.  Using one folder, users can store all information needed for a particular project, including all contacts, meetings, and background information.
• Document Management.  Automatic versioning, locking of documents during editing, saving from MS Office applications, and access from MS explorer.

3) Scalix (commercial and free versions available)

• Outlook Support.  Offers automatic offline mailbox caching and improved PDA syncing.
• Plug-in support.  Provides certified plug-ins support for Google Desktop and MSN Search, McAfee VirusScan, Symantec Norton Utilities and Captaris RightFax Outlook Extension.
• Search and Indexing Services.  Real-time indexing of private and public folder messages.  This results in sub-second mailbox-wide search and retrievals, even in very large mailboxes and folders. 

4) Citadel

• Ajax Support.  An intuitive, easy-to-use AJAX interface.
• Domain Management.  Multiple domain support.
• Easy Installation.  installs in minutes without the need to manually integrate all the different components together.

5) opengroupware

• Contact Management.  Saves and organizes thousands of personal and company contacts, telephone, fax, addresses, e-mail contact addresses just to mention a few. Easily configurable with extensive and speedy search capabilities, categorization and remotely accessible.
• Group Calendar.  Manage meetings and events for an entire group or individual set of accounts. Attach notes to appointments. Link appointments to contacts and projects. Automatic detection of conflicts.
• Resource Planner.  Keep track of your company’s resources such as automobiles, projectors or conference rooms. Searchable timeslots to check for availability of specific resources or resources assigned to a specific group. Automatically check for resource conflicts upon appointment creation.