Unified Communications SSL Certificates or Exchange SSL are built expressly for the Microsoft Exchange and/or Microsoft Office Communication Server environments.
Unlike standard or even Wildcard SSL Certificates, a single Exchange SSL Certificate can provide secured communications on a number of different domains, reducing administrative complexity and cost.
Unified Communications SSL certificates also support the 'Autodiscover' service in Microsoft Exchange, a new capability that greatly eases client administration.
A Comodo UC certificate is issued in minutes and is trusted by over 99.9% of major web browsers and mobile devices.