In between Color on UI Slider

In between Color on UI Slider


Hello,
Is there a way to set the in between color when having 2 anchors on
the the slider ?
Here is the example for the slider :
http://interface.eyecon.ro/demos/slider_minmax.html
In this example (based on jquery) as you slide the two anchors the
middle selected range is a different color :
http://www.filamentgroup.com/examples/slider/index2UI.php
How to do this in the normal interface.eyecon.ro slider ?
thanks.