private void createComboVariables()
{
combo_variables = ComboBox.NewText ();
variables = Util.StringToStringArray(Constants.UndefinedDefault);
UtilGtk.ComboUpdate(combo_variables, variables, "");
combo_variables.Active = UtilGtk.ComboMakeActive(variables, Catalog.GetString(Constants.UndefinedDefault));
combo_variables.Changed += new EventHandler (on_combo_other_changed);
UtilGtk.ComboPackShowAndSensitive(hbox_combo_variables, combo_variables);
}