function fn_FormataCep()
{
//usar no evento onkeypress

	//verifica se o caracter digitado está contido em goodChars
	goodChars = "0123456789-"
	caracDigit = String.fromCharCode(window.event.keyCode)
	if (goodChars.indexOf(caracDigit) == -1)	
		{window.event.returnValue = false}

	if (window.event.srcElement.value.length == 5 && window.event.keyCode != 8 && caracDigit != "-")
		window.event.srcElement.value += "-";
}