Pop quiz!
Q: What happens if you have a SMTPA server, and you have a user called info, and then set its password to info?
A:
[root@victim ~]# qmail-qstat messages in queue: 151369 messages in queue but not yet preprocessed: 9
Lesson:
Yes, there is a reason why those passwords are not available by default.
I really should limit the per-account outgoing mail by default in all servers. Let's start working on it.