eaptls certificate question

[Norbert Wegener]

My radius does an eaptls 802.1x authentication with looking into AD to 
get group information and finally consulting the users file,
to assign the correct vlan. This works without problems.
When I configure  another  certificate_file/private_key_file in 
eap.conf, the authentication process does not succeed.
The obvious difference between the working and the not working 
configuration is, that in the bad case, the certificate is issued by an 
intermediate ca, not by the root ca.
May this chaining have negative influence on the configuration?
If this is not the case,  maybe another reason may be found in

radiusd -AX's lengthy output: http://www.wegener-net.de/fr/typescript

Thanks
Norbert Wegener