for (i=0 ; i <= parent.nav.document.images.length; i++) {
   if (parent.nav.document.images[i]) {
      var ImageObject = eval(parent.nav.document.images[i])
 	  if (ImageObject.src.substr(ImageObject.src.length-16,16)=='bullet_arrow.gif') ImageObject.src="art/shim.gif"; 
   }
}
function SetBullet(what) {
eval("parent.nav.document."+what+".src='art/bullet_arrow.gif'")
}