HMC 4.5 brings together powerful Microsoft enterprise products such as Microsoft Exchange Server, Microsoft Windows SharePoint Services, and now gives you Microsoft Office Communications Server 2007, which manages all real-time communications such as instant messaging (IM) and audio and video conferencing.

Other new features and enhancements:

• Exchange Server 2007 SP1:  Web-based OABs and resource mailboxes
• Windows SharePoint Services:  multi-tenant People Picker functionality
• Provisioning capabilities have been expanded:
  • Microsoft Provisioning System (MPS)
    cross data store integration procedures
  • Individual Information Worker (IIW) tenant model
• New SDK, updated for HMC 4.5

Get started now with HMC 4.5 and HMC 4.5 SDK | Full Article