Paypal IPN custom variable is empty - php

Question

So I'm trying to send a custom variable with a Paypal adaptive payment and when Paypal does its IPN with the file that I specified in the selling preferences on my Paypal account, the custom variable is empty. My Curl code works fine and the response envelope returns successful. I echoed the post fields before sending them and this is what I got (sensitive data censored):
actionType=PAY&clientDetails.applicationId=[app
ID]&clientDetails.ipAddress=[my ip]
¤cyCode=USD&feesPayer=EACHRECEIVER&memo=[my
memo]&custom=1Ad2Ad8Ad9&receiverList.receiver(0).amount=1&receiverList.receiver(0).email=[email1]&receiverList.receiver(0).primary=true&receiverList.receiver(1).amount=0.2&receiverList.receiver(1).email=[email2]&receiverList.receiver(1).primary=false&receiverList.receiver(2).amount=0.19&receiverList.receiver(2).email=[email3]&receiverList.receiver(2).primary=false&receiverList.receiver(3).amount=0.16&receiverList.receiver(3).email=[email4]&receiverList.receiver(3).primary=false&requestEnvelope.errorLanguage=en_US&returnUrl=[return
url]&cancelUrl=[cancel url]
The custom variable is in tact and exactly as I want it. On the other hand I noticed that the currencyCode field was changed to "¤cyCode" somehow. I have no clue why but when I changed it to an array and used print_r, it said currencyCode.
Anyway the problem that I'm having comes up when Paypal does its instant notification to my Confirm.php and runs the following code:
// read the post from PayPal system and add 'cmd'
$req = 'cmd=_notify-validate';
foreach ($_POST as $key => $value) {
$value = urlencode(stripslashes($value));
$req .= "&$key=$value";
}
// post back to PayPal system to validate
$header = "POST /cgi-bin/webscr HTTP/1.0\r\n";
$header .= "Content-Type: application/x-www-form-urlencoded\r\n";
$header .= "Content-Length: " . strlen($req) . "\r\n\r\n";
$fp = fsockopen ('ssl://www.paypal.com', 443, $errno, $errstr, 30);
if (!$fp) {
// HTTP ERROR
} else {
fputs ($fp, $header . $req);
while (!feof($fp)) {
$res = fgets ($fp, 1024);
if (strcmp ($res, "VERIFIED") == 0) {
$strEmail = $_POST[ "payer_email" ];
if( isset( $_POST[ "custom" ] ) == true )
{
$strQuery = "UPDATE TTest SET TestField = 'posted: " . $_POST[ "custom" ] . "' WHERE id = 1";
}
// Execute
mysql_query( $strQuery );
}
else if (strcmp ($res, "INVALID") == 0) {
}
}
fclose ($fp);
}
The $_POST[ "custom" ] variable appears to be empty because it only sets TestField to "posted: " every time.