Visible, true with fade?

Hi all

I have a little problem with a flash movie. I want to create a sort of dropdown menu, and have used, woth on release visible true, and stuff. It works fine now, but then i found out that i wanted it to fade up, instead of just showing up suddenly. Is there an AS soloution to this? When i press the gallery button, the submenu fades up, and when i press another button, the previous will fade down, and a new submenu will fade up…

.fla file
.swf file