xkoto, the database virtualization start-up, has gotten another $3 million in financing from its backers, GrandBanks Capital and GrowthWorks Canadian Fund.

That makes a total of $13 million since it was founded in 2005. Apparently it's not a new round but an extension of its B round.

xkoto says it will use the money to build its sales force, accelerate customer acquisition and enhance its Gridscale database virtualization widgetry.

The company claims record 2008 sales, saying it added several global corporations as customers and closed the year with 275% growth in the fourth quarter. It says annual revenues were up 73% over 2007.

Major new customer wins include BNSF Railway, CNN, HSBC, Independence Blue Cross, Innovapost, Norfolk Southern Corporation, PUMA AG International, the Texas Department of Transportation and the Toronto Police Department.

Gridscale virtualizes the database infrastructure, distributing the application load horizontally across multiple instances of commercial databases running on clusters of low-cost hardware, mid-range systems and virtual machines. It offers lower costs, improved application performance and continuous availability for business-critical applications.

xkoto expanded its potential market when it rolled out Gridscale for SQL Server. It also released a new version of its flagship product for IBM DB2, which can support mixed operating systems and database versions in the same virtualized database pool, and synchronous and asynchronous database replication, reportedly guaranteeing zero data loss for remote databases.

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