XP Desktop Shortcut Start In

We are running an application from a master application server, and our users have individual desktop shortcuts pointing to the application. Each may have distinct “Start In” parameters. We would like to set a parameter in the application config file to point to these distinct “Start In” directories for user specific files, so that all user files are kept local. Does anyone know of a way to capture the individual “Start In” directory from, for example, a system environment variable? Thanks.