Is this possible?

[tnt at kalik.net]

>I want to use a freeradius server for the following purposes:
>
>- grant authorizaton to Cisco switches via LDAP (group membership checking, etc).

Yes.

>- make a WIFI with WPA+802.1x via MS IAS/RRAS (the main auth is done by the IAS, so the freeradius acts as client for IAS/RRAS, and the WIFI APs act as radclients for freeradius)
>- wired 802.1x via MS IAS/RRAS
>

Yes. Configure realm for IAS server in proxy.conf and freeradius as IAS
client. user at realm will then be proxied to IAS.