Setting focus?

have the following organistion of mc’s.

textArea_mc: contains an Input textfield named textBox

selector_mc: square shaped mc

main_mc: (Nested Clip)
selector_mc
textArea_mc

i’m doing hitTest and getting name of mc on which the mouse is there.
when it’s textArea_mc, i want to setfocus to it for editing text??
How???
Please Help me.
Thanx,