http://blockchain.info/api/api_receive says:
//Check the Request ip matches that from blockchain.info
if ($_SERVER['REMOTE_ADDR'] == '91.203.74.202') {
It seems the callback comes from 91.223.16.20 now, not 91.203.74.202. Is there a better way of checking the IP address so the callback handler doesn't need to be edited each time you move to a different server?
Also, a couple of typos on that page:
"will be past back" ->
passed back
"the server must check
the the callback" -> "that the"