Host Europe Group is moving 1.4 million mailboxes to Open-Xchange, the Germany-based supplier of open source groupware and messaging solutions that competes directly with Microsoft Exchange. Host Europe Group gets to move its UK and German customers off various aging messaging platforms and onto Open-Xchange’s AJAX-based web interface. And Open-Xchange gets a little closer to their goal of 40 million users by year’s end.

Right now, Host Europe Group has their hosted e-mail customers on a mishmosh of Atmail, Roundcube and SquirrelMail. But by the end of the year, the service provider hopes to finish switching all of them to the Open-Xchange groupware platform and Personal Information Management (PIM) solution, according to the press release. For no extra charge, those customers will find themselves with calendaring and contact management.

In that same press release, Host Europe Group cites Open-Xchange’s focus on value-added upsells as a major reason why they went with the  Open Xchange Hosting Edition platform. Mailboxes are cheap, but the ability to further monetize their customers with mobile device and software integrations can potentially give Host Europe Group the competitive edge they need to get ahead.

Open-Xchange has been building a lot of customer momentum in 2011, signing cloud and hosted service providers left and right. We’ll be watching closely to see if they can keep it up.

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