diff --git a/gluon/sqlhtml.py b/gluon/sqlhtml.py
index a030dd90..4f9a47ec 100644
--- a/gluon/sqlhtml.py
+++ b/gluon/sqlhtml.py
@@ -840,7 +840,7 @@ def formstyle_bootstrap(form, fields):
             controls.add_class('span4')
 
         if isinstance(label, LABEL):
-            label['_class'] += ' control-label'
+            label['_class'] = add_class(label.get('_class'),'control-label')
 
         if _submit:
             # submit button has unwrapped label and controls, different class
@@ -890,7 +890,7 @@ def formstyle_bootstrap3_stacked(form, fields):
                 e.add_class('form-control')
 
         if isinstance(label, LABEL):
-            label['_class'] += ' control-label'
+            label['_class'] = add_class(label.get('_class'),'control-label')
 
         parent.append(DIV(label, _controls, _class='form-group', _id=id))
     return parent
@@ -941,7 +941,7 @@ def formstyle_bootstrap3_inline_factory(col_label_size=3):
             elif controls is None or isinstance(controls, basestring):
                 _controls = P(controls, _class="form-control-static %s" % col_class)
             if isinstance(label, LABEL):
-                label['_class'] += ' control-label %s' % label_col_class
+                label['_class'] = add_class(label.get('_class'),'control-label %s' % label_col_class)
 
             parent.append(DIV(label, _controls, _class='form-group', _id=id))
         return parent
diff --git a/gluon/tools.py b/gluon/tools.py
index 63c8d3a2..6c94d75b 100644
--- a/gluon/tools.py
+++ b/gluon/tools.py
@@ -1423,9 +1423,9 @@ class Auth(object):
                  hmac_key=None, controller='default', function='user',
                  cas_provider=None, signature=True, secure=False,
                  csrf_prevention=True, propagate_extension=None,
-                 url_index=None):
+                 url_index=None, jwt=None):
 
-        ## next two lines for backward compatibility
+        ## next two lines for backward compatibility        
         if not db and environment and isinstance(environment, DAL):
             db = environment
         self.db = db
@@ -1543,7 +1543,7 @@ class Auth(object):
             self.define_signature()
         else:
             self.signature = None
-
+            
     def get_vars_next(self):
         next = current.request.vars._next
         if isinstance(next, (list, tuple)):