How can implement overloading in JavaScript/jQuery?

Im trying to call functions with same signature.

Example: There are two functions with same name:

<script>
    var obj1,obj2,obj3,obj4,obj5;
    function OpenBox(obj1,obj2){
    // code
    }
    function OpenBox(obj1,obj2,obj3,obj4,obj5){
    // code
    }
</script>

When I calling function on click event of link

<a id='hlnk1' href='#' onclick='OpenBox(this,\"abhishek\"); return false;'> Open Box </a>

When I click on the above link it is calling function OpenBox(obj1,obj2,obj3,obj4,obj5){}

It should be call function OpenBox(obj1,obj2){} Instead.

What's going wrong in functions?