A sample config with IAS is below.
http://www.cisco.com/warp/customer/110/cvpn3k_pix_ias.html
Does it work at all or it completely fails ?
Does it work if it is standalone ?
If it works with stand alone and not with
IAS on PDC/BDC, then from the same URL:
This is a very basic setup to use a Windows 2000 IAS server for RADIUS authentication of VPN users. If you require a more complex design, please contact Microsoft for assistance.