Hi, im having a problem loading a webpage inside a frameset. This frameset is inside an iframe.

when i click the link in menu, it creates an iframe that load a frameset page (with two frames), the upper frame loads a webpage, this webpage in the body onLoad calls a javascript and passes a name of a webpage that must load in the other frame, the problem im facing is in the javascript, it returns null.
this is the code.

function doLoad(url) {
      var iFrameContent = document.getElementById('iframeContenido');
	  iFrameContent.document.getElementsByName('statuszone') = url;
where 'iframeContenido' is the ID of the iframe that loads the frameset.
statuszone is the name tag of the frame where the url must be loaded.
this url is in the same domain.

why is this null?
any suggestions?

thanks in advance!