There're several folks asking for multiple-handle sliderMoveTo on the UI list:

http://groups.google.com/group/jquery-ui/browse_thread/thread/20db89aaad9836f0#

Kalath e-mailed me off-list and asked about it, and I wrote up a quick patch. It adds an extra parameter to sliderMoveTo

which is the (zero-based) index of the handle to move, so to move the 3rd handle to 40 you'd do:

$('#slider').sliderMoveTo(40, null, null, null, 2);

The patch moves most of the body of moveTo() into an inner function that takes the interaction handle, and then calls that function with either this.interaction (single handle) or this.interactions[which] (multiple handles). All the rest of the touched lines are indentation changes or this->self swaps to make the moveTo body work inside an inner function.

It's dependent upon bug #1737. The patches themselves are independent (and both should be applied), but sliderMoveTo doesn't work at all until #1737 is fixed.