Sorting all orders by USER NAME

When I sort (in either direction) orders by USER NAME, it's not accurately sorting from a-z or z-a. I opened a ticket to have this fixed (case #00097366). It was, but it only sorts the first page of results, not the entire list of orders, even if I click to the next page, they are resorted out of order. I was told this would be a code change. I believe this should be out of the box.

Steps: cimm2 prod > site manager > orders > order list > sort USER NAME column