function checkAll(checkname, sourcecheck)
{
	var checks = document.getElementsByName(checkname);

	for (i = 0; i < checks.length; i++)
	{
		checks[i].checked = sourcecheck.checked ? true : false
	}
}

function anyChecked(checkname)
{
	var checks = document.getElementsByName(checkname);

	for (i = 0; i < checks.length; i++)
	{
		if (checks[i].checked)
		{
			return true;
		}
	}

	alert("Please select at least one listing before you do this.");
	return false;
}