Log onto the webmail interface mail.math.uzh.ch
Go to Preferences > Mail > (scroll the big right window down) Receiving Messages > When a message arrives: Send auto-reply message: ...
Please be aware: Notifications will only be sent once a week per person. This means, if you send a testmail to yourself on Monday, you will receive the automatic reply. If you send a second testmail to yourself 5 days later, you will not!