Oracle Beehive alternatives

Oracle Beehive
Oracle Beehive provides an integrated set of communication and collaboration services built on a single scalable, secure, enterprise-class platform. Beehive allows users to access their collaborative information through familiar tools while enabling IT to consolidate infrastructure and implement a centrally managed, secure, and compliant collaboration environment built on Oracle technology.
Oracle Beehive alternatives are:
Google Apps, Microsoft Exchange, SharePoint, Zimbra