would this work...it's not, so I'm wondering if I'm missing something simple.
<?php
// HTTP authentication
$url = "https://secure.authorize.net/gateway/transact.dll";
//https://secure.authorize.net/gateway/transact.dll?x_Login=test&x_Version=3.1&x_Amount=3.00&x_Card_Num=4111111111111111&x_Exp_Date=0203&x_Type=AUTH_CAPTURE&x_Test_Request=TRUE&submit=yes&x_Test_Request=TRUE&x_Cust_ID=me&x_Invoice_Num=123&x_Relay_Response=TRUE&x_Relay_URL=https://66.26.4.224/test/curl.php";
$ch = curl_init();
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_USERPWD, "myusername:mypassword");
curl_setopt($ch, CURLOPT_POSTFIELDS, "x_Login=test&x_Version=3.1&x_Amount=3.00&x_Card_Num=4111111111111111&x_Exp_Date=0203&x_Type=AUTH_CAPTURE&x_Test_Request=TRUE&submit=yes&x_Test_Request=TRUE&x_Cust_ID=me&x_Invoice_Num=123");
$result = curl_exec($ch);
curl_close($ch);
echo $result;
?>
