CPackageSelectStructure::WizOnCheckBoxClick

function WizOnCheckBoxClick(checkbox)
			{
				var li = checkbox.parentNode;
				WizSelectAll(li, checkbox.checked);

				var systemPages = document.getElementById("system-pages");
				if (li.parentNode == systemPages || li.parentNode.parentNode.parentNode == systemPages)
					WizDisableCopyButton();
				else
					WizDisableButtons();
			}