function bairros() 
{
	
	var xmlHttp; 
	try 
	{
		// Firefox, Opera 8.0+, Safari
		xmlHttp=new XMLHttpRequest();
	}
	catch (e)
	{
		// Internet Explorer
		try
		{
			xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch (e)
		{
			try
			{
				xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
			}
			catch (e)
			{
				alert("Seu navegador não suporta AJAX!");
				return false;
			}
		}
	}
	xmlHttp.onreadystatechange=function()
	{     
		if(xmlHttp.readyState==4) 
		{     
			document.getElementById("idbairros").innerHTML = xmlHttp.responseText;   
		} 
		else
		{
			document.getElementById("idbairros").innerHTML = "<img src='./images/carregando.gif' />";  
		}
	} 
	var id = document.getElementById("id_cidade").value;
	xmlHttp.open("GET","./imoveis_bairros.php?id="+id,true); 
	xmlHttp.send(null);
}