Trying to use Josh Bush's masked input plugin.

I want to shift focus and do other things once the person puts their cell phone in. I mask to a phone shape. When I hit the last letter, I want it to trigger a javascript function. Right now that function just alerts hi. But I can't get it to work:

function jump(){
    alert('hi');
}

$(document).ready(function(){
    $("#cellphone").focus();
    jQuery(function($){
        $("#product").mask("(999) 999-9999",{completed:function(){jump();}});      
    });
 });