Simple movie clip button question

I am building a simple tabbed interface with 5 tabs, each showing different information. At the top of each tab, I am using a movie clip with an “off” and “on” state, so that when the tab is not selected, the text is grayed out and when it is selected, the text turns black. I have made it so that when the movie clip is clicked it goes to the right tab, using frame labels, but I can’t make it change from “off” to “on”. I know it is probably the most simple thing, but I need help finding the answer to this so I can move on.

Below is the AS i used to make one of the tab buttons work. Like I said, it changes the tab but doesn’t change itself.

on (release) {