During some recent customer customer meetings I’ve had a few customers asking for details of how to enable Certificate based authentication for Windows Mobile.
The Microsoft Exchange Server ActiveSync Certificate-Based authentication tool provides several utilities to assist an Exchange administrator in configuring and validating client certificate authentication for Exchange Server ActiveSync.
http://www.microsoft.com/downloads/details.aspx?FamilyId=82510E18-7965-4883-A8C3-F73F1F4733AC&displaylang=en