Smartphone and gadget makers in Japan can now get Microsoft's latest mobile operating system, ensuring that consumers will get a look at new software this summer, Microsoft said on Wednesday.

The Redmond, Wash.-based firm says 6 million gadgets with the Windows Mobile operating system were sold last year worldwide in 2006. It expects to sell 1 million gadgets with the software in Japan this year.

Four gadget makers have already committed to use the software in their products. The companies are Willcom, NTT DoCoMo, Softbank Mobile and eMobile.