Middleswarth

From the Postfix mailist.

If your version of Postfix supports pcre maps (it should), then the easy way out is here:

main.cf:
smtpd_sender_restrictions =
permit_mynetworks,
check_sender_access pcre:/etc/postfix/sender_access_pcre

pcre:/etc/postfix/sender_access_pcre:
/\.biz$/ 554 domain .biz not accepted as sender address

test with postmap:
postmap -q sender@xxxxxxxxxxx pcre:/etc/postfix/sender_access_pcre

To test pcre capability of your Postfix version: