Cisco ACS 5.3 and ProCurve 2510 with 802.1X and Mac-auth

[CSCO10235167]

Hey!

I am having difficulties implementing Mac-auth on selected ports between an HP ProCurve 2510 and Cisco ACS 5.3.The 802.1x works just fine, but for selected ports I need to implement port-access with MAC-based authentication instead of regular 802.1X (yeah, I know, but this line of ProCurve switches only support one auth-mechanism per port!).

The switch successfully forwards interesting MAC-auth requests for authentication to the ACS with CHAP/MD5, but the ACS reports this:

Logged At:	April 16,2012 1:20:48.080 PM
RADIUS Status:	Authentication failed : 22056 Subject not found in the applicable identity store(s).
NAS Failure:
Username:	002655886b3d
MAC/IP Address:	00-26-55-88-6b-3d
Network Device:	HP2510 : 192.168.0.51 : 5
Access Service:	MAB Access Service
Identity Store:
Authorization Profiles:
CTS Security Group:
Authentication Method:	CHAP/MD5

Evaluating Service Selection Policy

15004  Matched rule

15012  Selected Access Service - MAB Access Service

Evaluating Identity Policy

15006  Matched Default Rule

15013  Selected Identity Store -

22043  Current Identity Store does not support the authentication method; Skipping it.

22056  Subject not found in the applicable identity store(s).

22058  The advanced option that is configured for an unknown user is used.

22061  The 'Reject' advanced option is configured in case of a failed authentication request.

11003  Returned RADIUS Access-Reject

The ACS is configured to use the Internal Hosts database, where the client computer is configured like this;

MAC-address: 00-26-55-88-6B-3D

Anyone encountered this, or has any suggestions?