Keith,
I believe we have the same SP, I used the "Stub" attribute repository to release a set of static attributes.
Relevant section in my cas.properties looks something like this (Note: I use CAS 6.2):
#-----Stub (Static attributes)----------------------------------------------------------------------------------------------------#
#-----These are hardcoded attributes for B&N----------------------------------------------------------------------------------------------#
cas.authn.attribute-repository.stub.attributes.schoolName=<Name to be returned>
cas.authn.attribute-repository.stub.attributes.schoolNumber=<Number to be returned>