function updateSubCategorySelect()
	{
	var ParentEl = document.getElementById("MainCategorySelect");
	var SubEl = document.getElementById("SubCategorySelect");
	for(i=SubEl.length;i>=0;i=i-1)
		{
		SubEl.options[i] = null;
		}
	if(ParentEl[ParentEl.selectedIndex].value=='')
		{
		for(i=1;i<arraySubCategories.length;i++)
			{
			writeNewOption(arraySubCategories[i],SubEl);
			}
		}
	
	if(ParentEl[ParentEl.selectedIndex].value=='1')
		{
		for(i=1;i<arraySubCategories1.length;i++)
			{
			writeNewOption(arraySubCategories1[i],SubEl);
			}
		}
	
	if(ParentEl[ParentEl.selectedIndex].value=='3')
		{
		for(i=1;i<arraySubCategories3.length;i++)
			{
			writeNewOption(arraySubCategories3[i],SubEl);
			}
		}
	
	if(ParentEl[ParentEl.selectedIndex].value=='2')
		{
		for(i=1;i<arraySubCategories2.length;i++)
			{
			writeNewOption(arraySubCategories2[i],SubEl);
			}
		}
	
	if(SubEl.style.display=='none')
		{
		SubEl.style.display='';
		}
	}

function writeNewOption(strValue,El)
	{
	var newOption = new Option(strValue.substring(strValue.indexOf(':|:')+3,strValue.length),strValue.substring(0,strValue.indexOf(':|:')),false,false);
	var ElLength = El.length
	El.options[ElLength] = newOption;
	}