var removeFirstColourOption = true;
function updateSizes(comboList)
{
		var coldd = document.getElementById("cid");

		if (removeFirstColourOption == true)
		{
			//coldd.options[0].disabled = true;		// disable first option "----- select ----"
			coldd.remove(0);
			removeFirstColourOption= false;
		}
		
		var sizdd = document.getElementById("sid");
		if (sizdd.type == 'select-one')
		{
			sizdd.disabled = true;
			// remove all current options in the drop down
			while (sizdd.length > 0) { sizdd.remove(0); }
			
			var selColVal = parseInt(coldd.options[coldd.selectedIndex].value);
			//now load the size drop down if neccessary
			for (var i = 0; i < comboList.length; i++)
			{
				if (parseInt(comboList[i][0]) == selColVal)
				{
					sizdd.options[sizdd.options.length] = new Option(comboList[i][3], comboList[i][2]);
				}
			}
			
			// enable the size dropdown
			sizdd.disabled = false;
		}
		
}