shift-cmd-8 seems to be a different combination than what I posted above. I can add a new keyboard shortcut to toggle column selection as shift-cmd-8 and there are no conflicts so it is a good suggestion. I am still very curious what the original shortcut is supposed to be though.
Maybe the original keyboard combination requires a numpab which has the * key? Even so what is the little keyboard icon supposed to mean.
Meta (Command) + Shift + 8 (Mac OS X 10.5+ Keymap)
Meta (Command) + Shift + Numpad * (Mac OS X Keymap)