有关Json_encode()函数的问题

本人当前的php版本还没有Json_encode()函数，从网上下了json.class.php用来弥补。目的是想读取extjs2.2.1实例dataview中的图片，在实例中的get-images.php中添加下列语句：
function json_encode($array){
require_once("json.class.php");
$json = new Services_JSON;
$json_array = $json->encode($array);
return $json_array;
}再运行get-images.php后得到下列结果：
{"images":[{"name":"dance_fever.jpg","size":2067,"lastmod":1.22002665E+012,"url":"Images\/thumbs\/dance_fever.jpg"},{"name":"gangster_zack.jpg","size":2115,"lastmod":1.22002665E+012,"url":"Images\/thumbs\/gangster_zack.jpg"},{"name":"kids_hug.jpg","size":2477,"lastmod":1.22002665E+012,"url":"Images\/thumbs\/kids_hug.jpg"},{"name":"kids_hug2.jpg","size":2476,"lastmod":1.22002665E+012,"url":"Images\/thumbs\/kids_hug2.jpg"},{"name":"sara_pink.jpg","size":2154,"lastmod":1.22002665E+012,"url":"Images\/thumbs\/sara_pink.jpg"},{"name":"sara_pumpkin.jpg","size":2588,"lastmod":1.22002665E+012,"url":"Images\/thumbs\/sara_pumpkin.jpg"},{"name":"sara_smile.jpg","size":2410,"lastmod":1.22002665E+012,"url":"Images\/thumbs\/sara_smile.jpg"},{"name":"up_to_something.jpg","size":2120,"lastmod":1.22002665E+012,"url":"Images\/thumbs\/up_to_something.jpg"},{"name":"zack.jpg","size":2901,"lastmod":1.22002665E+012,"url":"Images\/thumbs\/zack.jpg"},{"name":"zacks_grill.jpg","size":2825,"lastmod":1.22002665E+012,"url":"Images\/thumbs\/zacks_grill.jpg"},{"name":"zack_dress.jpg","size":2645,"lastmod":1.22002665E+012,"url":"Images\/thumbs\/zack_dress.jpg"},{"name":"zack_hat.jpg","size":2323,"lastmod":1.22002665E+012,"url":"Images\/thumbs\/zack_hat.jpg"},{"name":"zack_sink.jpg","size":2303,"lastmod":1.22002665E+012,"url":"Images\/thumbs\/zack_sink.jpg"}]}应该说明已经读取到了图片信息
可页面图片数量依旧为0，不知何故，请各位指教，多谢