diff --git a/gen/__init__.py b/gen/__init__.py
index 35da42b..fa05a3c 100644
--- a/gen/__init__.py
+++ b/gen/__init__.py
@@ -1456,7 +1456,11 @@ class Boolean(Type):
                       label, sdefault, scolspan)
         self.pythonType = bool
 
+    # Layout including a description
     dLayouts = {'view': 'lf', 'edit': Table('flrv;=d', width=None)}
+    # Centered layout, no description
+    cLayouts = {'view': 'lf|', 'edit': 'flrv|'}
+
     def getDefaultLayouts(self):
         return {'view': 'lf', 'edit': Table('f;lrv;=', width=None)}
 
@@ -2925,6 +2929,8 @@ class Config:
         self.sourceLanguage = 'en'
         # Activate or not the button on home page for asking a new password
         self.activateForgotPassword = True
+        # Enable session timeout?
+        self.enableSessionTimeout = False
         # When using Ogone, place an instance of appy.gen.ogone.OgoneConfig in
         # the field below.
         self.ogone = None
diff --git a/gen/generator.py b/gen/generator.py
index 9bed045..8ab1a0b 100644
--- a/gen/generator.py
+++ b/gen/generator.py
@@ -603,6 +603,7 @@ class ZopeGenerator(Generator):
         repls['languages'] = ','.join('"%s"' % l for l in self.config.languages)
         repls['languageSelector'] = self.config.languageSelector
         repls['sourceLanguage'] = self.config.sourceLanguage
+        repls['enableSessionTimeout'] = self.config.enableSessionTimeout
         repls['ogone'] = repr(self.config.ogone)
         repls['activateForgotPassword'] = self.config.activateForgotPassword
         self.copyFile('config.pyt', repls, destName='config.py')
diff --git a/gen/installer.py b/gen/installer.py
index fb40242..cd60316 100644
--- a/gen/installer.py
+++ b/gen/installer.py
@@ -318,7 +318,11 @@ class ZopeInstaller:
         # Register a function warning us when a session object is deleted. When
         # launching Zope in test mode, the temp folder does not exist.
         if not hasattr(self.app, 'temp_folder'): return
-        self.app.temp_folder.session_data.setDelNotificationTarget(onDelSession)
+        sessionData = self.app.temp_folder.session_data
+        if self.config.enableSessionTimeout:
+            sessionData.setDelNotificationTarget(onDelSession)
+        else:
+            sessionData.setDelNotificationTarget(None)
 
     def enableUserTracking(self):
         '''Enables the machinery allowing to know who is currently logged in.
diff --git a/gen/templates/config.pyt b/gen/templates/config.pyt
index d4a5041..6da84f5 100644
--- a/gen/templates/config.pyt
+++ b/gen/templates/config.pyt
@@ -48,6 +48,7 @@ languages = [<!languages!>]
 languageSelector = <!languageSelector!>
 sourceLanguage = '<!sourceLanguage!>'
 activateForgotPassword = <!activateForgotPassword!>
+enableSessionTimeout = <!enableSessionTimeout!>
 ogone = <!ogone!>
 
 # When Zope is starting or runs in test mode, there is no request object. We