Vibrating Treo alerts?

Verizon Wireless Treo 650

A friend of mine has a Treo 650 with Verizon Wireless. He would like to
configure his alerts so when he gets a text message the phone vibrates (no
audio alarm), but when he receives email he would like no alert at all (no
sound, no vibrate). I see settings to set the alerts for MMS & SMS messages
but nothing for email. The SMS is set for vibrate only and that works great
but the email alerts seem "married" to the SMS serttings and do the same
thing. Is there a way to solve this problem?

Thanks in advance... Fred