When I send an email to email@example.com, I eventually get a response (this one took several days):
Hi. This is the qmail-send program at mail.codehaus.org. I’m afraid I wasn’t able to deliver your message to the following addresses. This is a permanent error; I’ve given up. Sorry it didn’t work out.
firstname.lastname@example.org: /usr/bin/env: ruby: No such file or directory I’m not going to try again; this message has been in the queue too long.