Not a lot to go one but the first possibility is, are they visible? The visible box must be checked in each ones settings. Have you created an overriding "look" command? or messed with the game attributes lately? Simple stuff, but that is the first thing to check and without more to go on, it's all I can think of for now.
Well, "look" directions are always visible when you "look" in there directions (unless you don't put a description in) ---- just the player's ability to "move" in those directions instead of just "look"ing are changeable.
The thing I've changed in the "look" directions was "look self" --- nothing else was changed and that was several updates ago and the "look" worked then.
No game attributes (that have to do with that) have been changed either that I've noticed.
Hmm.....I don't understand why it isn't working.