function validatesize()
{
	if (document.getElementById('size_small').checked || document.getElementById('size_medium').checked || document.getElementById('size_large').checked || document.getElementById('size_xlarge').checked || document.getElementById('size_xxlarge').checked)
	{
		return true;
	}
	else
	{
		alert('Please select a size.');
		return false;
	}
}