You can create directory handlers in the SA under the directory handlers link... a default directory handler that has all subscribers in it ships with Unity.
To get to it you can either map a one key dial option off a call handler (i.e. off the opening greeting) or you can assign an extension number to the directory handler and dial it directly (i.e. assign it "411" and let folks jump to it from any greeting they want).
Check your oepning greeting call handler under the "user input" page and make sure "4" is mapped to go to the directory handler - if it's not, you can change it there to do that.
