php模拟UA发说说显IPHONE，不行啊，为啥

我模拟了下‖
<?php
$sid="你的SID";
$qq="你的QQ";
 
$content=urlencode("说说发表了测试a啊");
$url="http://blog30.z.qq.com/mood/mood_add_exe.jsp?sid=$sid";
$post_data="content={$content}&B_UID={$qq}&come_from=mood_add_from_mood_my&action=1&c=2";
$userAgent="Mozilla/5.0(iPad;
 U;
 CPU iPhone OS3_2 like Mac OS X;
 en-us) AppleWebKit/531.21.10 (KHTML, likeGecko) Version/4.0.4 Mobile/7B314 Safari/531.21.10";
$curl=curl_init($url);
curl_setopt($curl,CURLOPT_RETURNTRANSFER,true);
curl_setopt($curl,CURLOPT_REFERER,$url);
curl_setopt($curl,CURLOPT_TIMEOUT,30);
curl_setopt($curl,CURLOPT_POST,true);
curl_setopt($curl, CURLOPT_USERAGENT,$userAgent);
curl_setopt($curl,CURLOPT_POSTFIELDS,$post_data);
 echo curl_exec($curl);
curl_close($curl);
?>