I have a multi module maven2 project. I'm using Hudson maven2 project to build
it. During the Hudson configuration for the maven2 project, I enabled the email
notification and input my email address in the recipients. Ideally if the build
fails, I would get an email about it. But somehow no email is sent when the
build fails. After some trial and error, I found that only when I manually queue
a build for the failed module in the maven project, a build failed email is
sent. I also tried to manually queue a build for the whole project but still no
email.

In the mailing list, it looks others are having similar issue:
http://www.nabble.com/Fail-to-send-email-notifciation-for-m2-project-tf4388766.html