More reliably extract user's email address.

lib/roles/auth.js

@@ -51,7 +51,7 @@ module.exports = function(options) {
             log.info('Authenticated "%s"', user.userPrincipalName)
             var token = jwtutil.encode({
               payload: {
-                email: user.userPrincipalName
+                email: ldaputil.email(user)
               , name: user.cn
               }
             , secret: options.secret

lib/util/ldaputil.js

@@ -109,3 +109,8 @@ module.exports.login = function(options, username, password) {
       })
   })
 }
+
+// Export
+module.exports.email = function(user) {
+  return user.mail || user.email || user.userPrincipalName
+}