private void handleEnumeration(Attributes atts) {
			if (currentSimpleType != null && currentSimpleType.variable != null) {
				if (currentSimpleType.variable instanceof StringVariable
						&& (currentSimpleType.variable.getConstraint() == null ||
						    currentSimpleType.variable.getConstraint() instanceof ValidStringValues)) {
					ValidStringValues constraint;
					constraint = (ValidStringValues)currentSimpleType.variable.getConstraint();
					if (constraint == null) {
						constraint = new ValidStringValues();
						currentSimpleType.variable.setConstraint(constraint);
					}
					constraint.addValidValue(atts.getValue("value"));
				}
			}
		}