I'm having a problem with sending bounces to spammers when a remote "trusted" smtp server rejects a mail. My server manages mail for company1.com that has a virtual alias support@company1.com that delivers mail to a bunch of local users but also to the support@company2.com that is managed by the other team. Their mail system implements a different (better if you will) spam protection and can reject mails after DATA.
The problem is when a spammer reaches through and postfix on company1.com mail server tries to deliver mail to support@company2.com it gets
554 Transaction failed. Unacceptable content. (in reply to end of DATA command)
and generates a bounce message to the spammer. So the question is how do I prevent it from doing that? In fact I'm not interested in generating any bounce messages for company2.com at all so a large hammer would work too since my mail server doesn't handle any other mail for company2.com.
Thanks in advance.