1. Press Sign up
2. Enter details and press the sign up button
3. Press log in
4. Enter username / password from step 2 and click Log In
5. On the "Account is not activated" page, enter a new email into the field and press Update email
Zanata displays a success message, but on the server an exception has occurred (and no email was actually sent). Intermittently.
Firefox on F22, Wildfly 10.0, Zanata 3.9 release candidate 1 (dbe9cb6a6572752622f86e114796ccb48626de4b)