Skype has released versions of Skype 2.2 for both Windows Mobile for Pocket PC and Smartphone. It adds support for Windows Mobile 6.1 as well as a host of new bug fixes and smaller enhancements. Among the latter are improved voice quality, a new Today screen plug-in, the ability to retrieve forgotten passwords and more.
Minimum requirements are Windows Mobile 2003 or higher, a 195MHz OMAP or 312MHz Intel processor, 12MB of free storage (or 6MB if installing from a memory card), and network connectivity. Also ensure that your display is supported. For example, 320×320 is not supported at this time.
Windows Mobile Skype 2.2 is available for free directly from Skype.