Hierarchical select term is not sortable under table settings in a custom view page

I've ran into a small problem whenever I try to list a Hierarchical term in a View page. I've created a field and assigned the field type as a Term Reference and the widget as Hierarchical Select. So now I've listed this field under a table on a custom View page and I noticed that other fields have the option to be sortable in this table except for the Hierarchical Term reference. So far no one has complained but I know for a fact that users will want to sort out this column via alphabetical terms in the future.

Is this a coding bug that hasn't been reported before or is this a feature that hasn't been added to this module yet? Any insight will help.