As your module is doing a good job, you might consider adding a filter that converts user@domain.com to user-78c1ed6da0322b3a@domain.com, where the added hex string contains the encrypted timestamp and remote ip-address of the address harvester.

If one receives spam to such an address, he knows the IP address of the harvester and can try to prosecute the spammer.

See Anti-Spam Mail Address Encoding (with encrypted IP-Address) for two subs doing the encoding/encrypting

alex pleiner <alex@zeitform.de>
zeitform Internet Dienste