diff --git a/tryton/client.py b/tryton/client.py
index 82d0583f22..6c4f2ae97a 100644
--- a/tryton/client.py
+++ b/tryton/client.py
@@ -116,8 +116,7 @@ class TrytonClient(object):
                 gtk.main()
         except KeyboardInterrupt:
             CONFIG.save()
-            if hasattr(gtk, 'accel_map_save'):
-                gtk.accel_map_save(os.path.join(get_config_dir(), 'accel.map'))
+            gtk.accel_map_save(os.path.join(get_config_dir(), 'accel.map'))
 
 if __name__ == "__main__":
     CLIENT = TrytonClient()
diff --git a/tryton/common/common.py b/tryton/common/common.py
index 20ad7918ca..6cb1c56fde 100644
--- a/tryton/common/common.py
+++ b/tryton/common/common.py
@@ -633,12 +633,8 @@ class WarningDialog(UniqueDialog):
     def build_dialog(self, parent, message, title, buttons=gtk.BUTTONS_OK):
         dialog = gtk.MessageDialog(parent, gtk.DIALOG_DESTROY_WITH_PARENT,
             gtk.MESSAGE_WARNING, buttons)
-        if hasattr(dialog, 'format_secondary_markup'):
-            dialog.set_markup('<b>%s</b>' % (to_xml(title)))
-            dialog.format_secondary_markup(to_xml(message))
-        else:
-            dialog.set_markup(
-                '<b>%s</b>\n%s' % (to_xml(title), to_xml(message)))
+        dialog.set_markup('<b>%s</b>' % (to_xml(title)))
+        dialog.format_secondary_markup(to_xml(message))
         return dialog
 
 warning = WarningDialog()
diff --git a/tryton/common/completion.py b/tryton/common/completion.py
index 2f5b3d702b..441d422fdd 100644
--- a/tryton/common/completion.py
+++ b/tryton/common/completion.py
@@ -17,8 +17,7 @@ def get_completion():
     completion.set_match_func(lambda *a: True)
     completion.set_model(gtk.ListStore(str, int))
     completion.set_text_column(0)
-    if hasattr(completion.props, 'popup_set_width'):
-        completion.props.popup_set_width = False
+    completion.props.popup_set_width = False
     completion.insert_action_markup(0, _('<i>Search...</i>'))
     completion.insert_action_markup(1, _('<i>Create...</i>'))
     return completion
diff --git a/tryton/common/date_widget.py b/tryton/common/date_widget.py
index ded569d8cb..569e1f6df7 100644
--- a/tryton/common/date_widget.py
+++ b/tryton/common/date_widget.py
@@ -61,11 +61,10 @@ class DateEntry(gtk.Entry):
         self.connect('focus-in-event', self._focus_in)
         self.connect('focus-out-event', self._focus_out)
 
-        if hasattr(self, 'set_icon_from_stock'):
-            self.set_icon_from_stock(gtk.ENTRY_ICON_SECONDARY, 'tryton-find')
-            self.set_icon_tooltip_text(gtk.ENTRY_ICON_SECONDARY,
-                _('Open the calendar <F2>'))
-            self.connect('icon-press', DateEntry.cal_open)
+        self.set_icon_from_stock(gtk.ENTRY_ICON_SECONDARY, 'tryton-find')
+        self.set_icon_tooltip_text(gtk.ENTRY_ICON_SECONDARY,
+            _('Open the calendar <F2>'))
+        self.connect('icon-press', DateEntry.cal_open)
 
         self._interactive_input = True
         self.idle_set_position(0)
diff --git a/tryton/gui/main.py b/tryton/gui/main.py
index eb8c32f3c2..fe5e3a24c6 100644
--- a/tryton/gui/main.py
+++ b/tryton/gui/main.py
@@ -130,8 +130,7 @@ class Main(object):
         gtk.accel_map_add_entry('<tryton>/Form/Search', gtk.keysyms.F,
             gtk.gdk.CONTROL_MASK)
 
-        if hasattr(gtk, 'accel_map_load'):
-            gtk.accel_map_load(os.path.join(get_config_dir(), 'accel.map'))
+        gtk.accel_map_load(os.path.join(get_config_dir(), 'accel.map'))
 
         self.tooltips = common.Tooltips()
 
@@ -293,8 +292,7 @@ class Main(object):
         text_cell = gtk.CellRendererText()
         global_search_completion.pack_start(text_cell)
         global_search_completion.add_attribute(text_cell, "markup", 1)
-        if hasattr(global_search_completion.props, 'popup_set_width'):
-            global_search_completion.props.popup_set_width = True
+        global_search_completion.props.popup_set_width = True
         self.global_search_entry.set_completion(global_search_completion)
         self.global_search_entry.set_icon_from_stock(gtk.ENTRY_ICON_PRIMARY,
             'gtk-find')
@@ -1090,8 +1088,7 @@ class Main(object):
         CONFIG['client.default_width'] = Main.get_main()._width
         CONFIG['client.default_height'] = Main.get_main()._height
         CONFIG.save()
-        if hasattr(gtk, 'accel_map_save'):
-            gtk.accel_map_save(os.path.join(get_config_dir(), 'accel.map'))
+        gtk.accel_map_save(os.path.join(get_config_dir(), 'accel.map'))
 
         cls.tryton_client.quit_mainloop()
 
@@ -1186,8 +1183,7 @@ class Main(object):
         label_menu = gtk.Label(page.name)
         label_menu.set_alignment(0.0, 0.5)
         self.notebook.insert_page_menu(page.widget, hbox, label_menu, page_id)
-        if hasattr(self.notebook, 'set_tab_reorderable'):
-            self.notebook.set_tab_reorderable(page.widget, True)
+        self.notebook.set_tab_reorderable(page.widget, True)
         self.notebook.set_current_page(page_id)
 
     def _sig_remove_book(self, widget, page_widget):
diff --git a/tryton/gui/window/view_form/view/form_gtk/calendar.py b/tryton/gui/window/view_form/view/form_gtk/calendar.py
index 7292c7e0cc..c3c767d513 100644
--- a/tryton/gui/window/view_form/view/form_gtk/calendar.py
+++ b/tryton/gui/window/view_form/view/form_gtk/calendar.py
@@ -89,8 +89,7 @@ class Time(Calendar):
 
     def __init__(self, field_name, model_name, attrs=None):
         super(Time, self).__init__(field_name, model_name, attrs=attrs)
-        if hasattr(self.entry, 'set_icon_from_stock'):
-            self.entry.set_icon_from_stock(gtk.ENTRY_ICON_SECONDARY, None)
+        self.entry.set_icon_from_stock(gtk.ENTRY_ICON_SECONDARY, None)
 
     def get_format(self, record, field):
         return field.time_format(record)
diff --git a/tryton/gui/window/view_form/view/form_gtk/dictionary.py b/tryton/gui/window/view_form/view/form_gtk/dictionary.py
index 42090b8ff3..f958067a15 100644
--- a/tryton/gui/window/view_form/view/form_gtk/dictionary.py
+++ b/tryton/gui/window/view_form/view/form_gtk/dictionary.py
@@ -104,8 +104,7 @@ class DictSelectionEntry(DictEntry):
         widget.set_text_column(0)
         widget.child.set_width_chars(width)
         completion = gtk.EntryCompletion()
-        if hasattr(completion, 'set_inline_selection'):
-            completion.set_inline_selection(True)
+        completion.set_inline_selection(True)
         completion.set_model(model)
         widget.child.set_completion(completion)
         completion.set_text_column(0)
diff --git a/tryton/gui/window/view_form/view/form_gtk/selection.py b/tryton/gui/window/view_form/view/form_gtk/selection.py
index 8eb24f44e7..c5ad774088 100644
--- a/tryton/gui/window/view_form/view/form_gtk/selection.py
+++ b/tryton/gui/window/view_form/view/form_gtk/selection.py
@@ -29,9 +29,7 @@ class PopdownMixin(object):
         entry.set_model(model)
         entry.set_text_column(0)
         completion = gtk.EntryCompletion()
-        #Only available in PyGTK 2.6 and above.
-        if hasattr(completion, 'set_inline_selection'):
-            completion.set_inline_selection(True)
+        completion.set_inline_selection(True)
         completion.set_model(model)
         entry.child.set_completion(completion)
         if self._selection:
diff --git a/tryton/gui/window/view_form/view/list_gtk/parser.py b/tryton/gui/window/view_form/view/list_gtk/parser.py
index 847f780e49..c04e6deb9d 100644
--- a/tryton/gui/window/view_form/view/list_gtk/parser.py
+++ b/tryton/gui/window/view_form/view/list_gtk/parser.py
@@ -938,9 +938,7 @@ class Selection(Char, SelectionMixin):
         if hasattr(editable, 'set_text_column'):
             editable.set_text_column(0)
         completion = gtk.EntryCompletion()
-        #Only available in PyGTK 2.6 and above.
-        if hasattr(completion, 'set_inline_selection'):
-            completion.set_inline_selection(True)
+        completion.set_inline_selection(True)
         completion.set_model(model)
         editable.get_child().set_completion(completion)
         completion.set_text_column(0)
diff --git a/tryton/gui/window/view_form/view/screen_container.py b/tryton/gui/window/view_form/view/screen_container.py
index c6c7f26f6a..ca5d47763d 100644
--- a/tryton/gui/window/view_form/view/screen_container.py
+++ b/tryton/gui/window/view_form/view/screen_container.py
@@ -103,10 +103,8 @@ class ScreenContainer(object):
         self.completion.set_model(gtk.ListStore(str))
         self.completion.set_text_column(0)
         self.completion.props.inline_completion = True
-        if hasattr(self.completion.props, 'inline_selection'):
-            self.completion.props.inline_selection = True
-        if hasattr(self.completion.props, 'popup_set_width'):
-            self.completion.props.popup_set_width = False
+        self.completion.props.inline_selection = True
+        self.completion.props.popup_set_width = False
         self.completion.set_match_func(lambda *a: True)
         self.completion.connect('match-selected', self.match_selected)
         self.search_entry.connect('activate', self.activate)
@@ -431,8 +429,7 @@ class ScreenContainer(object):
             self.search_window.set_title('Tryton')
             self.search_window.set_icon(TRYTON_ICON)
             self.search_window.set_decorated(False)
-            if hasattr(self.search_window, 'set_deletable'):
-                self.search_window.set_deletable(False)
+            self.search_window.set_deletable(False)
             self.search_window.connect('key-press-event', key_press)
             vbox = gtk.VBox()
             fields = [f for f in self.screen.domain_parser.fields.itervalues()
diff --git a/tryton/gui/window/win_form.py b/tryton/gui/window/win_form.py
index 314bff6630..015628e45f 100644
--- a/tryton/gui/window/win_form.py
+++ b/tryton/gui/window/win_form.py
@@ -38,8 +38,7 @@ class WinForm(NoModal):
         self.win.set_position(gtk.WIN_POS_CENTER_ON_PARENT)
         self.win.set_icon(TRYTON_ICON)
         self.win.set_has_separator(False)
-        if hasattr(self.win, 'set_deletable'):
-            self.win.set_deletable(False)
+        self.win.set_deletable(False)
         self.win.connect('close', self.close)
         self.win.connect('response', self.response)
 
diff --git a/tryton/gui/window/wizard.py b/tryton/gui/window/wizard.py
index 869ec06f98..3e37106691 100644
--- a/tryton/gui/window/wizard.py
+++ b/tryton/gui/window/wizard.py
@@ -295,8 +295,7 @@ class WizardDialog(Wizard, NoModal):
             gtk.DIALOG_DESTROY_WITH_PARENT)
         self.dia.set_position(gtk.WIN_POS_CENTER_ON_PARENT)
         self.dia.set_icon(TRYTON_ICON)
-        if hasattr(self.dia, 'set_deletable'):
-            self.dia.set_deletable(False)
+        self.dia.set_deletable(False)
         self.dia.connect('close', self.close)
         self.dia.connect('response', self.response)
         self.dia.connect('state-changed', self.state_changed)