DatePicker in UI 1.5.1 does not cancel button click

In the latest jquery UI, 1.5.1, I use a date picker using the following options:

{ dateFormat: 'yy-mm-dd', showOn: 'button', buttonText: '…' };

This renders a button correctly next to the input box.

However, clicking the button causes the page to submit.

If I return false in the trigger, then this problem goes away.

For example, the current code is this in the DatePicker :

(Line 345)

trigger.click(function() {

if ($.datepicker._datepickerShowing && $.datepicker._lastInput == target)

$.datepicker._hideDatepicker();

else

$.datepicker._showDatepicker(target);

});

If I simply add return false after the if/else, then it works.