function trim(str){
	if(!str || typeof str != 'string'){
		return "";
	}
	return str.replace(/^[\s]+/,'').replace(/[\s]+$/,'').replace(/[\s]{2,}/,' ');
}
function validate(){
	var password = trim(window.document.rform.password.value);
	if(trim(window.document.rform.login.value) == ''){
		alert('Escriba o seu nome de usuario');
		window.document.rform.login.focus();
		return false;
	}
	else if (trim(window.document.rform.password.value) == ''){
	    alert('Introduza a súa contraseña');
		window.document.rform.password.focus();
		return false;
	}
	else{
		window.document.rform.login.value = trim(window.document.rform.login.value);
		window.document.rform.password.value = password;
		return true;

	}
}