function verificaEmailExistenteAjax(campo, tipo) {

		var url = '/usuario/contato.jscale';

		var parametros ='acao=verificaEmailExistenteAjax&email=' + campo.value +'&tipoCadastro=' + tipo.value;

		var req = initRequest(url);
		
		req.open('POST', url, true);
		req.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
		req.setRequestHeader('Content-length', parametros.length);

		req.onreadystatechange = function() {
			if (req.readyState == 4) {
				if (req.status == 200) {

					document.getElementById('v_email').innerHTML = '';
							
				}
				if (req.status == 500){
					document.getElementById('v_email').innerHTML = req.responseText;
		
				}				
			}

		}

		req.send(parametros);  	
	}