Use of email address as a persistent identifier for the DSpace conflicts with the fact that email addresses are not persistent. Email addresses go away and/or are reassigned to other individuals. There are also policy concerns with Authenticators like Shibboleth and CAS that may or may not deliver an email address as a organizational policy.
This Task is a placeholder to identify a solution to correct for the problem.
1.) DSpace should use a different identifier / key for the EPerson (netid? or combination of "authenticator + netID")
2.) DSpace should make providing an email address as optional for cases where the Authentication features lack this specific capability.
3.) Issuing emails should be optional for accounts without email addresses.
4.) Stop storing email address (or any other detail about who made the change) in dc.description.provenance field.
One proposed solution to this problem is that the Authentication Method should be broken off of EPerson and stored separately, making EPerson a "Profile" and the method of Authentication be stored separately (Password, Certificate, LDAP, Shibboleth, CAS, Facebook, Google) Different AuthenticationMethods may store the data as they see fit. And the Profile would store only those local details for that user.