RAS book can be created in two ways in windows CE either through Dial up and network wizard
or through programmatically. Although Microsoft provides sample
application for creating a RAS book in Windows CE 6.0, still it is not
clearly answering on how to add some specific parameters to establish
GPRS connectivity.Please See the below link for more details...
http://www.e-consystems.com/blog/windowsce/?p=846
http://www.e-consystems.com/blog/windowsce/?p=846