When you select the textField DropShadow occurs?

Its pretty simple but I don’t know how to do it.

I have a file with first name, middle initial, last name.

I have created 3 text fields inside of mc’s and 3 mc’s for the “text field borders”.

I would like for the first mc aka fn_box to have a DropShadow when the first textField mc is either rolledOver or selected.

I have attached the file but I don’t even know where to begin.

I think its something along these parameters…but don’t quote me…lol

fn_txt_mc.onRollOver {fn_box.filters [DropShadowFilter,3,3];}
How would I write this in AS 2 and AS 3?