Nokia’s deal to outsource Symbian development to Accenture was finalised on Wednesday, after the two companies reached an agreement to handover software development and support to the outsourcing company.

The terms of the agreement state that Accenture will support Symbian development and support at least until 2016, providing a lifeline for the stricken operating system. Nokia will transfer 2,800 of its employees from North America, Asia and Europe when the deal is closed, which will likely take place in October 2011.

Accenture will also provide its services to Nokia with the development of its new Windows Phones, working with Avanade (a service company that is majority-owned by Accenture) which provides assistance on Microsoft technologies.

“Our collaboration with Accenture allows us to meet our ongoing commitment to support our Symbian smartphone customers and continue to leverage the talent that has the deepest experience on the platform,” said Jo Harlow, executive vice president for Smart Devices, Nokia. “As we move our primary smartphone platform to Windows Phone, we will look to explore potential opportunities to tap this talent pool as they develop and expand their knowledge and capabilities beyond Symbian.”