Nokia today announced it has acquired Enpocket, the Boston-based mobile advertising company, for an undisclosed sum, marking its entrance into the still-nascent mobile ad space.

Nokia officials said Enpocket delivers services and technology that will enable Nokia to plan, design, execute, optimize and measure mobile ad campaigns all around the globe. Enpocket’s technology allows for the delivery of mobile advertising across various formats including SMS, MMS, mobile, Internet advertising and video.

Nokia’s acquisition of Enpocket is the latest of many in its quest to become a leader in the consumer Internet services arena. Enpocket joins the ranks of Loudeye, Intellisync, Twango, gate5 AG and several other companies acquired by Nokia in the past few years. This latest purchase advances Nokia’s strategic shift from handset maker to service provider. It comes only a week after its launch of online portal Ovi, which brings together Nokia’s new gaming portal, music store, mapping, social networking and other mobile applications.

"Nokia has already announced its intention to be a leading company in consumer Internet services, and we believe that mobile advertising will be an important element in monetizing those services for our customers and partners,” Tero Ojanpera, Chief Technology Officer for Nokia, said in a statement. “Enpocket's mature leading edge platform and people expertise are a strong fit with Nokia existing capabilities in the mobile advertising market. This acquisition is a game-changing move to bring the reach and depth of Nokia to organize the market across the world and make it easier for an ecosystem to develop."

From the acquisition, Nokia will gain access to Enpocket’s partnerships with advertisers, publishers and operators, as well as to a staff of 100 Enpocket employees. Conversely, Nokia now has a mobile advertising business to match wits against competitors also entering the mobile arena, including Third Screen Media, owned by AOL; Screentonic, owned by Microsoft and AdMob, financed by Sequoia Capital.

Financial details of the deal, which is expected to close in the fourth quarter of this year, have not yet been released.