clients can't authenticate in FR 2.0.3

Hi again. Please Help me. I'm very desperate. I want to put a freeradius 2.0.3 why i need to connect a Windows XP, Vista and CE. But when I to configure the freeradius-1.1.3-1.2.el5 (rpm) it works fine. My windows XP and CE clients connect without problems, but I need urgently to connect a Windows Vista clients too. Please HELP ME. Alan Dekok, do you have any suggest? Or do you know any HOW TO based over FR 2.0.3?