function trimString(value)
{
	if (value.length>0)
	{
		// trim leading spaces
		while(''+value.charAt(0)==' ') value=value.substring(1,value.length);
	}
	if (value.length>0)
	{
		// trim trailing spaces
		while(''+value.charAt(value.length-1)==' ') value=value.substring(0,value.length-1);
	}
	return value;
}

function isEmpty(field)
{
	field = trimString(field);
	
	if (field == "")
	{
		return true;
	} else {
		return false;	
	}
}