CAS protocol and trackSPSessions true

[Scott Koranda]

Hi,

I am using IdP version 3.1.1 configured for both SAML2 and CAS
protocol flows.

I noticed that if I set 

idp.session.trackSPSessions = true

in idp.properties

then CAS clients receive 

<cas:authenticationFailure code="INTERNAL_ERROR">E_ILLEGAL_STATE</cas:authenticationFailure>

and the IdP logs

2015-06-18 08:54:35,492 - ERROR [net.shibboleth.idp.session.impl.StorageBackedIdPSession:412] - Exception saving SPSession record for IdP session cdc7fff9bf2d41d395cf868daa7e25b7ebf738ea8b1613c3efdeed3bbe1c0f74 and service https://myhost/secure/
java.io.IOException: No serializer registered for SPSession type net.shibboleth.idp.cas.session.CASSPSession
        at net.shibboleth.idp.session.impl.StorageBackedIdPSession.saveSPSessionToStorage(StorageBackedIdPSession.java:657)
2015-06-18 08:54:35,493 - WARN [net.shibboleth.idp.cas.flow.UpdateIdPSessionWithSPSessionAction:92] - Failed updating IdP session with CAS SP session: Exception saving SPSession record to storage

Is this expected?

Thanks,

Scott K