If table column only contains numeric values (such as IP addresses), sorting does not work for that column

I have a table that lists network devices with IP addresses. It would be useful to be able to sort by IP address so I can view devices per subnetwork.

However, it seems that Confluence fails to sort if there are no letters in that column.

Case in point: I tried adding a letter ("c" in my case) to any cell in that column and sorting worked. After removing the letter, sorting did not work.

I don't have access to this Confluence instance's logs at the moment, but I'm fairly sure Confluence runs into an exception when trying to sort this column.

To reproduce:

1. Copy this into a Confluence page and try to sort by the different columns.

   Device	IP	Location
   A	192.168.0.1	New York
   B	192.168.1.1	Los Angeles

   You should see that sorting by 'Device' or 'Location' works fine, while sorting by 'IP' does not.

2. Add a letter after either IP. Now try sorting by that column again. Sorting should now work.