by Tony Galvão.
Hi dude,
I had the same problem. In my case the problem was the theme ... I decided just commenting the lines of the custom menu;
$siteadmin = $topsettings->settings_tree($this->page->settingsnav);
risible_position_menus($siteadmin, $navigation, $hascustommenu, $custommenu, $home);
Sorry my english done by Google Translate.
I hope help you.