I have the same problem.
Paypal orders getting back with a validation failure:
"Validation error: PayPal IPN response from a different email address (my@mail.com). Order status changed from pending to on-hold."
in my langues:
Valideringsfejl: PayPal IPN-svar fra en anden e-mail-adresse (my@mail.dk). Ordrestatus ændret fra Afventer betaling til På Hold.