If you are using Maven 2, email notifiers configured in pom.xml will be automatically added, and you may have as many as you need.
<ciManagement>
<system>continuum</system>
<notifiers>
<notifier>
<configuration>
<address>email adress</address>
</configuration>
</notifier>
</notifiers>
</ciManagement>
Or can you can manually add mail notifiers at the project group or individual project level.
On the Add Notifier form select Mail from the pull-down menu and click Submit.

You must either provide a single email address, or select to notify the latest committers.
In addition you may select one or more "Send on..." options.
Then, click Save.