Ok, so

[code]
this.serviceRequest = new Mojo.Service.Request("palm://com.palm.vibrate", {
method: 'vibrate', parameters: { 'period': 0,'duration': 250 }
});
[/code]

seems to work!

I inserted into the function

[code]
if (notificationData.keys().length > 0 && this.Messaging.messagingPrefs.enableNotification) {
[/code]

first thing, before

[code]
var notificationType = notificationData.get('notificationType');
[/code]

Set the duration to 1500, and now my phone vibrates for 1.5 seconds when I get a txt. Not a very strong vibrate, but it works.