Sony Ericsson is rolling out the seventh version of Walkman mobile phones — cellular phones that also include music playback capabilities.

The latest, the W300, is a clamshell phone designed to work with enhanced data networks known as EDGE. It can store up to 30 hours of music and supports both MP3 and AAC playback formats. The phone also includes an FM radio.

Also included is digital camera and a 256 megabyte memory stick that can be expanded to one gigabyte.

The phone will be available in the second quarter of this year.

Sony Ericsson: