방법1----------------------------------

function ccc(talk){
 alert(talk);
} 

function addEvent(object, event ,listener)
{
    if (object.addEventListener){
        object.addEventListener(event, listener, false);
    } else if (object.attachEvent){

        object.attachEvent('on' + event, listener);
    }
}
addEvent(window,'load',new Function("ccc('가')"));





방법2----------------------------------
function addOnload(f) {

     var nowonload = window.onload;

     if (typeof window.onload != 'function') {

          window.onload = f;

     }

     else {

          window.onload = function() {

               if (nowonload) {

                     nowonload();

                   }

               f();

           }

      }

}

addOnload(function() {

     xxx();

});