We use the gemalto .NET smart card with rdesktop and it works with Windows 2003/2008 Servers (Linux & Mac). But we are not able to use a Windows 2008 R2 Server. Users get the following error message from Windows when they insert the card: No vaild certificates found, Check that the card is inserted correctly and fits tightly. The smartcards are ok. Valid certificates, working with Windows 2003 and Windows 2008.