How is it possible to use OrderingLinks to define sort order on multiple
columns of the same name.

EG:

select a.desc first_desc, b.desc second_desc from main x
join descriptions a on a.id = x.id1
join descriptions b on b.id = x.id2;

I want the user to be able to search on a.desc or b.desc, but I can't figure
out the OrderingItems syntax that will allow it. I can arrange for the
initial sort to use a.desc or b.desc OK, but the grid does not recognize
that either column can be ordered, so the user can't change the order by
clicking on the title bar.

Any help gratefully appreciated,

Thanks,

Brian