[otrs] Drop/Ignore emails with manipulated FROM headers

Hi all, I'm sure many of you have encountered this case with some of your customers/vendors/partners. Sometimes when we email a certain customer, their ticketing system sends back an email with a manipulated FROM header, sending back what we originally sent. Let me break this down. Our company is www.example.com. We send an email to www.abc.com. Our sender address is support@example.com, and their's is support@abc.com. Original email: From: "EXAMPLE SUPPORT" To: "ABC SUPPORT" Subject: WHATEVER Body: "Bla Bla Bla" Return email (almost instantly): From: "EXAMPLE SUPPORT" To: "EXAMPLE SUPPORT" Subject: Re:WHATEVER Body: "Bla Bla Bla" Is it possible to drop or ignore this email? In other words, which Postmaster filter should be applied to query for both the name and the address? Thanks //M