A friend got this from paypal:
The thing is that he uses the standard paypal module, "PayPal Website Payments Standard".
and there is no such file there "standard_ipn.php"
What I did is to look up for a new paypal module, and I found this one:
http://addons.oscommerce.com/info/7184
Downloaded it, but it doesn't contain such a file as well..
osc_PayPal_v180\catalog\ext\modules\payment\paypal
only rp_ipn.php and express.php
How to handle this?