function addOnload(x){
      var nowOnload = window.onload; // Let's save the existing assignment, if any
      window.onload = function () {
        // Here is your precious function
        // You can call as many functions as you want here;
        x();

        // Now we call old function which was assigned to onLoad, thus playing nice
        if(nowOnload != null && typeof(nowOnload) == 'function') {
            nowOnload();
        }
      }
    }