Problem with events

I have a main class which listens for an event dispatched from another class say class A.
Also there are other classes say class B, class C etc.
There is a controller class.
Classes B, C dispatches events that gets listened by the controller and works well.

But the events dispatched by the Class A doesn’t get listened by the main class.
What might be the problem.

Detailed Explanation of the problem.
There is a main mxml file.
Class files are in:
ProcessInput.as
DBController.as
ShortMemDB.as …etc

The main mxml file gets the input from a textArea. Sends the input to the capturedInput(input:String) function using set method which is in the ProcessInput Class.

Now I need to dispatch events NORMAL, COMMAND depending on the input obtained after the processing, where I’m having problems. The reason is that if the event NORMAL is dispatched a particular function inside the DBController is to be called. If COMMAND event is dispatched then I need to call another function. This idea doesn’t work since the events doesn’t get listened.
But the events dispatched by the CSDB class when listened by the DBController works well.
So why does some events works and others don’t.

Googling about this has arrived at http://www.kirupa.com/forum/showthread.php?t=315911
But I’m not getting it.
Please help.