In the past week or so my Treo has started beeping two or three times when pressing the hard button for the phone and also for the mail button.

It beeps three times when pressing the phone button when the Treo is off.
It beeps three times when it's been on, but switching to the phone application.

Switching to the mail button (which has been programmed for SnapperMail) gives one beep.

It did it for a while last week, stopped, and then started it again.

What's my Treo trying to tell me?