Datepicker does not work in FF & Safari with "body { overflow:scroll }"

A vertical CSS scrollbar causes a bug ( seems to be a dimension problem )

This bug can easily be reproduced by copying the sample code of jqueryUI and adding 2 lines css declarations:

 body { overflow:scroll }
 #datepicker{ position:absolute; right:1px }

The result is here: http://jsbin.com/obami/ (Click at the textbox located on the right side)

The right part of the calendar is not clickable as it is out of the window and using the x-axis scrollbar hides the calendar.

Bug can be seen using on Mac OS X with Firefox 3.5, Safari 4.0, Opera 9.2

and with Windows using Firefox 3.5

Internet Explorer does not cause this bug ( probably because the vertical scroll bar is always shown )