function subnavEventHandlers () {
  if (document.layers && document.portfoliosubnav) {   
  document.portfoliosubnav.onmouseover = function (evt) {
        changeObjectVisibility('portfoliosubnav','visible');
      }
  document.portfoliosubnav.onmouseout = function (evt) {
        changeObjectVisibility('portfoliosubnav','hidden');
	  }
  }
  
  if (document.layers && document.homesubnav) {   
  document.homesubnav.onmouseover = function (evt) {
        changeObjectVisibility('homesubnav','visible');
      }
  document.homesubnav.onmouseout = function (evt) {
        changeObjectVisibility('homesubnav','hidden');
	  }
	}
}