Settings/Sounds and notifications/notifications. Pull the drop down menu that says incoming call. Go to new email message, select the option for vibrate. Click ok and should work. I have the notifications set to a certain way by default that is different from stock ROMs. Hope this helps you.
Thanks for the response, but while this does cause it to vibrate, it causes it to vibrate all the time (ie even when I have text/email notifications silenced at night).
What is really bizarre is if I have the screen on it will vibrate when a new Outlook message arrives, but if i turn the screen off and get an email nothing happens (but the LED starts blinking so I know the message has arrived). If anyone else's phone has experienced this problem with Outlook email and knows how to fix it any help is appreciated...