Why did Implementing HTTP/1.1 break my PayPal IPN script?

Here is the original code I had in my PHP script:

$header = "POST /cgi-bin/webscr HTTP/1.0\r
";
$header .= "Content-Type: application/x-www-form-urlencoded\r
";
$header .= "Content-Length: " . strlen($req) . "\r
\r
";


I got an official email from Paypal saying that I needed to upgrade my IPN script so that it uses HTTP/1.1. So here is what I changed my code to, based on their directions:

[COLOR=#333333][FONT=Arial]$header .="POST /cgi-bin/webscr HTTP/1.1\r
";
$header .="Content-Type: application/x-www-form-urlencoded\r
";
$header .="Host: www.paypal.com\r
";
$header .="Connection: close\r
";

Payments have gone through today, as I can see them on paypal’s website, but the IPN is no longer working. Any ideas on what to do?

Thanks!
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