Just how do you set up sendmail to deny Email with a Date header also much from live?
Sendmail isn't efficient filtering system messages by itself.
Theoretically it would not take much to write a straightforward
milter (sendmail mail filter) plugin to do simply that work.
Nonetheless if spam avoidance is the key need, after that why not go the entire hog and also plugin a complete anti - spam system?
Sendmail profanes ;) One remedy can be to install SpamAssassin and also incorporate it with spamass-milter right into your post. This has the benefit that you can turn on great deal of various other Anti - Spam regulations. Or simply write your very own plugins which is actually very easy.