cleartext passwords against Active Directory

[Leese, MJ (Mark)]

Hi,

I need to authenticate employees at my lab onto our wireless network
using a Captive Portal and our corporate database (Active Directory).
The Access-Request from the Captive Portal contains a cleartext password
but our Active Directory does not store cleartext passwords. Can someone
please tell me what options I have? Is it possible to use rlm_krb, for
example?

I have used our RADIUS server to authenticate users against our Active
Directory, but this was with ntlm_auth for users using 802.1X and
MS-CHAP.

Someone suggested I could authenticate the user with an LDAP bind, but I
don't see how this would work.

I'm running FreeRADIUS 1.1.4 but I can update to a newer version any
time.

Please help. I am running out of hair :)

Thanks in advance,

Mark.