function isValidEmail(str) {
  	 	return (str.indexOf(".") > 2) && (str.indexOf("@") > 0);
 	}
 	
 	function trim(str) {
 		return str.replace(/^(\s+)?(.*\S)(\s+)?$/, '$2');
 	}
 	
										
	 function validateEmail(str) {
		if(!(isValidEmail(str))) {
			alert('Please enter a valid email address.');
			return false;
		} else {
			return true;
		}
	 }
	 
	 function validateLoginForm(form) {
	 
	 	if(!(trim(form.user.value).length > 0)) {
	 		alert("Please enter a valid user name.");
	 		return false;
	 	}
	 	
	 	if(!(trim(form.pass.value).length > 0)) {
	 		alert("Please enter a valid password.");
	 		return false;
	 	} 	
	 	
	 	return true;	 	
	 	
	 }