diff --git a/src/calibre/gui2/catalog/catalog_csv_xml.py b/src/calibre/gui2/catalog/catalog_csv_xml.py
index b44f2d4c6a..3b2b25a800 100644
--- a/src/calibre/gui2/catalog/catalog_csv_xml.py
+++ b/src/calibre/gui2/catalog/catalog_csv_xml.py
@@ -11,15 +11,17 @@ from calibre.gui2 import gprefs
 from calibre.gui2.catalog.catalog_csv_xml_ui import Ui_Form
 from PyQt4.Qt import QWidget
 
-class PluginWidget(QWidget,Ui_Form):
+class PluginWidget(QWidget, Ui_Form):
 
     TITLE = _('CSV/XML Output')
     HELP  = _('Options specific to')+' CSV/XML '+_('output')
     sync_enabled = False
 
-    def initialize(self, name):
-        QWidget.__init__(self)
+    def __init__(self, parent=None):
+        QWidget.__init__(self, parent)
         self.setupUi(self)
+
+    def initialize(self, name):
         self.name = name
         # Restore the activated fields from last use
         for x in range(self.db_fields.count()):
diff --git a/src/calibre/gui2/dialogs/catalog.py b/src/calibre/gui2/dialogs/catalog.py
index 447cab68cc..9c004d9b07 100644
--- a/src/calibre/gui2/dialogs/catalog.py
+++ b/src/calibre/gui2/dialogs/catalog.py
@@ -17,7 +17,6 @@ from calibre.customize.ui import catalog_plugins
 
 class Catalog(QDialog, Ui_Dialog):
     ''' Catalog Dialog builder'''
-    widgets = []
 
     def __init__(self, parent, dbspec, ids):
         import re, cStringIO
@@ -40,7 +39,7 @@ class Catalog(QDialog, Ui_Dialog):
         # GwR *** Add option tabs for built-in formats
         # This code models #69 in calibre/gui2/dialogs/config/__init__.py
 
-        self.fmts = []
+        self.fmts, self.widgets = [], []
 
         from calibre.customize.builtins import plugins as builtin_plugins
 
@@ -99,9 +98,9 @@ class Catalog(QDialog, Ui_Dialog):
                 else:
                     info("No dynamic tab resources found for %s" % name)
 
-        self.widgets = sorted(self.widgets, key=lambda x:(x.TITLE, x.TITLE))
+        self.widgets = sorted(self.widgets, cmp=lambda x,y:cmp(x.TITLE, y.TITLE))
         for pw in self.widgets:
-            self.tabs.addTab(pw,pw.TITLE)
+            self.tabs.addTab(pw, pw.TITLE)
 
         # Generate a sorted list of installed catalog formats/sync_enabled pairs
         fmts = sorted([x[0] for x in self.fmts])