Enterprises adopting Windows Mobile 5.0 Smartphone Edition for road warriors can now integrate a 
VPN (virtual private network) system, certified by Microsoft Corp., for secure and stable access to their applications. Microsoft has certified NetMotion Wireless Inc.’s Mobility XE for use with its OS for advanced mobile phones such as the Cingular Wireless Inc. 2125 model. The VPN product, a combination of client and server software, encrypts data exchanged during enterprise application sessions and keeps the server sessions alive when the phone leaves a coverage area or roams to another network. The employee can then return to the task at hand when the wireless link is re-established.
Smartphones may be smaller than full-blown PDAs (personal digital assistants), but they still offer the ability to use enterprise applications while on the road, staying connected via a high-speed cellular network. VPN cavalry coming to Windows smartphones | InfoWorld | News | 2006-06-26 | By Stephen Lawson, IDG News Service