function isEmail(object)
{

	var inputstr = object.value;
	
	if(inputstr.length > 0)
	{
		
		var regex = /^.+\@(\[?)[a-zA-Z0-9_\-\.]+\.([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$/;
		
		if(regex.test(inputstr))
		{
			return true;		
		}
		else
		{
			return false;
		}
	}
	return true;
}