function select_atversion(){ 
    global $sort_versions;
    $menu = '<form action="'.$_SERVER['PHP_SELF'].'" method="post">'; 
    $menu.= '<select name="atversions">';
    $menu.= '<option value="0">'._AT("all").'</option>';
    foreach($sort_versions as $version){
        if($version == VERSION){
            $menu .= '<option value="'.$version.'" selected="selected">'.$version.'</option>';
        }else{
            $menu .= '<option value="'.$version.'" >'.$version.'</option>';
        }
    }
    $menu .='</select>';
    $menu .='<input type="submit"  value="'. _AT('filter').'"/></form>';
    return $menu;
}
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