If u want zoom on a text on Flash, then do the following:

1. Create text in the middle of your movie area.
2. Right-click (Mac: Ctrl-click) on frame 40. And Select Insert Keyframe.
3. Click on frame 1. Go to the Frames Panel. For Tweening select Motion
4. Right- Click (Mac: CTRL+CLICK) on frame 20 and select Insert Key Frame
5. Select the text and go to Modify>Transform>Scale & Rotate. Enter 900 for Scale and click Ok.
6. Contol>Rewind and then Control>Play. Finished.