How to manage multiple buttons with single Event handler; like Toolbar

Hi,

i have to design one Toolbar using Knockout (observableArray); i have
uploaded my sample on jsFiddler at below location:
http://jsfiddle.net/vikasjain/Eyrpz/

i designed one sample; which i am using in my application; its working fine
on IE9; when i run on IE8 then click on Add button after that all event
automatically fired.
i need your help; please look into my code if there is anything missing..