I think it's neccessary for you to create a new project in VS.NET 2005
under Smart Device --> PPC 2003 ("A project for creating a .NET Compact
Framework 2.0 forms application for Pocket PC 2003 and later"). Then
copy all your classes to the created directory, include them in the
project, reference the corresponding DLLs and try to compile! And Good
luck of course!
Hope that helps.
Regards.