Why mousewheel.js/Jscrollpane.js ( scrolloing using mouse wheel ) not working in Firefox?

It might be because of Jscrollpane.js issue.

The Quick solution to solve this issue is to edit the Jscroolpane.js.

Go to particular line number ( Mostly:341 )

and change to

var dragOffset = $drag.offset(false);
currentOffset = { top: dragOffset.top, left:dragOffset.left };
currentOffset.top -= dragPosition;