On the DHCP Panel, clicking on IP address causes entries to be ordered in ascending or descending order, but it does not sort them in numerical order.
For example in my case, the sort order for descending is 10.20.30.51, 10,20.30.5, 10.20.30.40.
In other words, it does not interpret 10.20.30.5 as 10.20.30.005 for sorting purposes.