--- wp-includes/functions.php.orig	2005-10-04 14:40:59.000000000 -0400
+++ wp-includes/functions.php	2005-10-04 14:41:51.000000000 -0400
@@ -802,7 +802,7 @@
 	if ( !isset( $parts['port'] ) )
 		$parts['port'] = 80;
 
-	$head = "HEAD $file HTTP/1.1\r\nHOST: $host\r\n\r\n";
+	$head = "HEAD $file HTTP/1.1\r\nHOST: $host\r\nUser-Agent: WordPress/" . $wp_version . " PHP/" . phpversion() . "\r\n";
 
 	$fp = @fsockopen($host, $parts['port'], $err_num, $err_msg, 3);
 	if ( !$fp )