如何使用php curl从iconcontact获取联系人

我正在尝试使用php脚本获取我在iconcontact帐户的联系人列表。我可以通过输入标题集，url和按下go来获取使用RestClient的联系人列表，所以我很确定我的标题和url是正确的。iContact为这个任务提供了示例代码，但是当我运行它(使用我的帐户和ap详细信息)时，我得到与运行以下代码时相同的响应:

<?php
    $Headers = array(
                "Accept: text/xml",
                "Content-Type: text/xml",
                "API-Version: 2.2",
                "API-AppId: grBddgWuirhAYT41K6gvrvRGaUGJFVQL",
                "API-Username: <removed>",
                "API-Password: <removed>");
    $Url = "https://app.sandbox.icontact.com/icp/a/412608/c/123920/contacts";
    $Handle    = curl_init();
    if(!$Handle)
    {
        die("Could not create a cURL handle.");
    }
    curl_setopt($Handle, CURLOPT_URL, $Url);
    curl_setopt($Handle, CURLOPT_HTTPHEADER, $Headers);
    curl_setopt($Handle, CURLOPT_USERAGENT, "Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.15) Gecko/20110303 Ubuntu/10.04 (lucid) Firefox/3.6.15");
    curl_setopt($Handle, CURLOPT_RETURNTRANSFER, true);
    $Response = curl_exec($Handle);
    $iCode = curl_getinfo($Handle);
    echo "Response: <br />";
    print_r($Response);
    echo "<br /><br /><br /><br /><br /><br /><br /><br /><br /><br />";
    echo "Code: <br />";
    print_r($iCode);
    curl_close($Handle);
?>

输出:

Response:

Code:
Array ( [url] => https://app.sandbox.icontact.com/icp/a/412608/c/123920/contacts [content_type] => [http_code] => 0 [header_size] => 0 [request_size] => 0 [filetime] => -1 [ssl_verify_result] => 0 [redirect_count] => 0 [total_time] => 0.094 [namelookup_time] => 0 [connect_time] => 0.094 [pretransfer_time] => 0 [size_upload] => 0 [size_download] => 0 [speed_download] => 0 [speed_upload] => 0 [download_content_length] => -1 [upload_content_length] => -1 [starttransfer_time] => 0 [redirect_time] => 0 ) 

根据我对curl的理解(目前不是很多)，http_code应该是200,xml应该在$Response中。

iconcontact的例子可以在这里找到:http://developer.icontact.com/documentation/code-library-zip-file/

我正在尝试做get_contacts.php应该做的