replaceImages = new Array(
  'Home|botao_home.gif',
  'Empresa|botao_empresa.gif',
  'Obras|botao_obras.gif',
  'Serviços|botao_servicos.gif',
  'Clientes|botao_clientes.gif',
  'Contato|botao_contato.gif',
  'Edifícios|icone_edificios.gif'
  );
/*
	firdom()
	written by Chris Heilmann (http://www.onlinetools.org)
*/
function firdom(){
	if(document.getElementsByTagName && document.createElement){
		as=document.getElementsByTagName('a');
		scanandreplace(as,'a');
	}
}
function scanandreplace(as,tag){
	for(i=0;i<as.length;i++){
		for(f=0;f<replaceImages.length;f++){
			chunks=replaceImages[f].split('|');
			thisa=document.getElementsByTagName(tag)[i];
			if(thisa.firstChild.nodeValue==chunks[0]){
				newImg=document.createElement('img');			
				newImg.setAttribute('alt',chunks[0])
				if (thisa.parentElement && thisa.parentElement.id == 'atual') {
					chunks[1] = 'desabilitado_' + chunks[1];
				}
				newImg.setAttribute('src',chunks[1])
				thisa.replaceChild(newImg,thisa.firstChild)
				/*if (thisa.firstChild.alt != 'Home'){
					thisa.onmouseover = function(thisa) { 
						this.firstChild.org = this.firstChild.src;
						this.firstChild.setAttribute('src', this.firstChild.over);
					}
					thisa.onmouseout = function(thisa) { 
						this.firstChild.setAttribute('src', this.firstChild.org);
					}
				}*/
			}
		}
	}
}
window.onload=firdom;