PayPal IPN Issues?

Hi all, I built a PHP PayPal IPN script a couple of months ago and has been working perfectly until today, PayPal just doesn’t seem to be firing the script. Does anyone know of any problems or the best thing to do about this? I have not changed the script. Tried looking to see if PayPal has made any changes but been unsuccessful.

I have checked the IPN history and they all say today ‘Retrying’.

post your ipn script otherwise I’d be only guessing as to what the cause of the problem is.