Class file linkage issue

Here is what I have…

MC_B is inside MC_A

MC_A is linked to class “Test” from Test class contains public function setAlpha();

Inside setAlpha(), I have:

MC_B_IdentifierName._alpha = 0;  //keep in mind that MC_B is inside MC_A

MC_A is attached to the stage by an onRelease event of MC_C, which are all defined inside another class that is linked to MC_C. So the code inside the OnRelease event is:

var item:MovieClip = this.attachMovie("MC_A", "InstanceofMC_A"+i, i+21, {_x:xPos, _y:420});

So At runtime, MC_C is first attached to the stage, then I click on it which attaches MC_A and calls setAlpha(). The error I’m getting at that point is:

There is no property with the name ‘MC_B_IdentifierName’.

I don’t know why setAlpha isn’t able to see MC_B_IdentifierName given that MC_A is linked to the class setAlpha is a public member of.

Any ideas why? THanks!