Just how Microsoft ( MSFT) plans to challenge Apple Computer's ( AAPL) iPod line is becoming a little clearer. Some specifications for the software giant's upcoming Zune digital-media player came out in a filing made with the Federal Communications Commission on Thursday. Among the details: Toshiba will make the device for Microsoft; it will have a built-in wireless networking antenna and an FM radio tuner; it will have a 30-gigabyte hard drive and a 3-inch screen. In contrast, Apple's 30-GB iPod has a 2.5-inch screen and doesn't come with either an FM tuner or a wireless antenna. Users can, however, buy an FM tuner add-on for the iPod. And the company offers customers the choice of some six other iPod models. A Microsoft representative confirmed that Toshiba will be manufacturing the Zune device and that the specifications in the regulatory filings are accurate. A representative for Toshiba did not return calls seeking comment. CNET News.com first confirmed that Toshiba will be making the device for Microsoft. As it's indicated before, Microsoft has big plans for the wireless networking feature. According to the filing, Zune users will be able to send songs, photos, playlists and albums to other Zune devices. And users will be able to act as a virtual disc jockey using a feature that allows them to stream music to up to four other Zune devices.