private ClassInfo canonizeIfaceRef(ClassInfo clazz, Reference ref) {
		while (clazz != null) {
			if (clazz.findMethod(ref.getName(), ref.getType()) != null)
				return clazz;
			ClassInfo[] ifaces = clazz.getInterfaces();
			for (int i = 0; i < ifaces.length; i++) {
				ClassInfo realClass = canonizeIfaceRef(ifaces[i], ref);
				if (realClass != null)
					return realClass;
			}
			clazz = clazz.getSuperclass();
		}
		return null;
	}