Adding the flags "once" or "once unique" to a callbacks object seems to disable the ability of .fired() to accurately reflect whether or not it was fired at least once. It always returns false, no matter how many times you fire the callback (it will only fire its functions once, obviously, but at that point it should be flagged as fired/resolved). This means that there is no simple way to tell if a callback has fired already (which is useful for triggering other loosely coupled behavior).

http://jsfiddle.net/XmPze/27/

Same (wrong?) behavior in both 1.7 and 1.7.1