Federated Trust Failing. Handing out null tokens

Hi,

I'm trying to setup an Exchange Federation with another org.  Everything is working for them connecting to us, but when I try to connect to them, I'm seeing a failure at the federated trust level.  A test-organizationalrelation fails at getting a token, and here is the results of a test-federationtrust.

STEP 5 of 6: Requesting delegation token...
RESULT: Success. Token retrieved.

Closing Test-FederationTrust...


RunspaceId : 3bbc82ce-e086-403e-b838-066d1aebed8e
Id         : FederationTrustConfiguration
Type       : Success
Message    : FederationTrust object in ActiveDirectory is valid.

RunspaceId : 3bbc82ce-e086-403e-b838-066d1aebed8e
Id         : FederationMetadata
Type       : Success
Message    : The federation trust contains the same certificates published by the security token service in its
             federation metadata.

RunspaceId : 3bbc82ce-e086-403e-b838-066d1aebed8e
Id         : StsCertificate
Type       : Success
Message    : Valid certificate referenced by property TokenIssuerCertificate in the FederationTrust object.

RunspaceId : 3bbc82ce-e086-403e-b838-066d1aebed8e
Id         : StsPreviousCertificate
Type       : Success
Message    : Valid certificate referenced by property TokenIssuerPrevCertificate in the FederationTrust object.

RunspaceId : 3bbc82ce-e086-403e-b838-066d1aebed8e
Id         : OrganizationCertificate
Type       : Success
Message    : Valid certificate referenced by property OrgPrivCertificate in the FederationTrust object.

RunspaceId : 3bbc82ce-e086-403e-b838-066d1aebed8e
Id         : TokenRequest
Type       : Error
Message    : Failed to request delegation token.

Error. Attempted to get delegation token, but token came back as null.
    + CategoryInfo          : NotSpecified: (:) [], LocalizedException+ FullyQualifiedErrorId : [Server=MailServer01,RequestId=df04b6d4-9357-425a-a6a7-682fb8e24086,TimeStamp=11/11/2014
    5:22:11 PM] 80737601+ PSComputerName        : CASServer01.subdomain.localdomain.com

When I created a federation trust namespace, it was created as subdomain.localdomain.com because that's where our Exchange servers live.  However all users have UPN's and email addresses of just "localdomain.com".  That said, after getting these errors, I changed an accounts UPN to user@subdomain.localdomain.com and added the same as an email address.  Still no joy.  Anybody have any suggestions?  Thanks!