Open-Xchange has closed a Series B round of venture funding totaling $9 million.

The company will use the funds to further develop its software and continue expanding its business in the U.S., Europe and emerging markets.

The round was led by eCAPITAL entrepreneurial Partners AG, a Munster , Germany-based, high-growth IT (Information Technology) equity firm. Also participating are Munich-based, BayBG, and existing Munich-based investor, BayTech Venture Capital. Frank Hoelzle, managing partner at eCAPITAL, will join the Open-Xchange board of directors. Terms of the financing deal were not disclosed.

Built as open source software, Open-Xchange is an alternative to commercial email/collaboration platforms like Microsoft Exchange and SharePoint providing an equivalent user experience with features like mobility support (iPhones, Blackberry), document sharing, shared calendars and shared address books. The software facilitates effective teamwork by improved communications.

"We're at a point of unprecedented growth in our company's history and will use these funds to help us add another 10 million mailboxes next year," said R afael Laguna, CEO of Open-Xchange. "As the lifeblood of every organization no matter what size, email and collaboration are going through a phase of dramatic change in many cases to hosted delivery and software as a service."

In September, new versions of Open-Xchange software were announced for both hosted and on-premise implementations. The company also recently announced agreements with O3SIS and Funambol that enable Internet Service Providers (ISPs), telcos and web hosting companies, as well as on-premise customers to offer end users the ability to access email from mobile phones. In May, Open-Xchange signed a broad cooperative agreement with Parallels to integrate its software. Parallels management and automation software is the definitive standard for ISPs and web hosting companies.

Open-Xchange received a total of $8.8 million in a Series A financing round from Business Angels and BayTech Venture Capital in 2006, shortly before the launch of its product with its first hosting customer 1&1 in February 2007.