diff --git a/gluon/tools.py b/gluon/tools.py
index bf4bd902..edccc825 100644
--- a/gluon/tools.py
+++ b/gluon/tools.py
@@ -775,8 +775,8 @@ class Mail(object):
                 if attachments:
                     result = mail.send_mail(
                         sender=sender, to=origTo,
-                        subject=to_unicode(subject, encoding), 
-                        body=to_unicode(text or '', encoding), 
+                        subject=to_unicode(subject, encoding),
+                        body=to_unicode(text or '', encoding),
                         html=html,
                         attachments=attachments, **xcc)
                 elif html and (not raw):
@@ -794,7 +794,7 @@ class Mail(object):
                 try:
                     raw = {'Data': payload.as_string()}
                     response = client.send_raw_email(RawMessage=raw,
-                                                     Source=sender, 
+                                                     Source=sender,
                                                      Destinations=to)
                     return True
                 except ClientError as e:
@@ -2161,7 +2161,10 @@ class Auth(AuthAPI):
         user = None
         checks = []
         # make a guess about who this user is
-        for fieldname in ['registration_id', 'username', 'email']:
+        guess_fields = ['registration_id', 'username', 'email']
+        if self.settings.login_userfield:
+            guess_fields.append(self.settings.login_userfield)
+        for fieldname in guess_fields:
             if fieldname in table_user.fields() and \
                     keys.get(fieldname, None):
                 checks.append(fieldname)
@@ -2255,7 +2258,8 @@ class Auth(AuthAPI):
     def _get_login_settings(self):
         table_user = self.table_user()
         userfield = self.settings.login_userfield or 'username' \
-            if 'username' in table_user.fields else 'email'
+            if self.settings.login_userfield or 'username' \
+            in table_user.fields else 'email'
         passfield = self.settings.password_field
         return Storage({'table_user': table_user,
                         'userfield': userfield,
@@ -3630,7 +3634,7 @@ class Auth(AuthAPI):
             onaccept = self.settings.profile_onaccept
         if log is DEFAULT:
             log = self.messages['profile_log']
-        
+
         form = SQLFORM(
             table_user,
             self.user.id,