用Imail Antivirus可以做到的。<br>
Blocking by total message size <br><br>Block messages that are larger than bytes <br><br>Blocking by subject line <br><br>Block messages with any of the following subject lines (one per line): <br><br>Block messages with empty subject lines <br><br>Blocking by message origin <br><br>Block messages that originate from the following email addresses or domains (one per line): <br><br><br>Blocking by attachment file name <br><br>Block attachments with any of the following file names (one per line): <br><br>When a matching attachment is found: <br>Delete the attachment <br>Reject the message <br><br>Blocking by attachment file size <br><br>Block attachments that match any of the file sizes specified below (one per line, in bytes): <br><br>When a matching attachment is found: <br>Delete the attachment <br>Reject the message <br><br>Updating mail message body <br><br>Add text to body of infected MIME-encoded messages to warn recipient of infections. <br><br>Blocking MIME partial message content <br><br>Block MIME partial message content <br>