By Lydia Leong

Hot on the heels of a day of rumors, VMware announced the acquisition of Zimbra, the open-source email platform vendor previously purchased (and up until now, still owned by) Yahoo!.

It’s a somewhat puzzling acquisition. Its key strategic thrust seems to be enabling the service provider ecosystem. Most service providers (i.e., hosters) already offer email as a service — although today, they primarily offer Hosted Exchange. Other platforms — Open-Xchange, OpenWave, Critical Path, Mirapoint, etc. — are used for more commodity email services. Relatively speaking, Zimbra doesn’t have as much traction in the service provider space, and VMware’s service provider ecosystem is not gasping for lack of reasonable platforms on which to offer email SaaS.

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