Does anyone know how to use Crystal Version 6 with windows authentication ?

Details:
VB6 apps with SQL2005 database and Crystal Reports Version 6

Currently the Reports log on to SQL with a userid and password.

Our legacy VB6 apps are being changed to use Windows Authentication. The only outstanding issue is to get the reports to work with authentication. There is a trusted connection check box but I have no idee how to use it.

Any coding examples ple?