HAIL stands for Hildon Accessibility Implementation Library. This is basically a GAIL extension, in the same way that Hildon is a widget extension to Gtk+. HAIL provides the a11y support for the Hildon widgets, included the new and fancy widgets created for Fremantle, the old libhildondesktop1 and the hildon file manager.
At last, just comment that Cally development is still in process, some bugs were resolved this months. Right now I’m working on the text changed, caret-moved and focus events management, and there is already a branch with a first solution.