Custom Scroll Button

[FONT=Trebuchet MS]I have a dynamic textbox I would like to scroll.

Currently I have 2 images set to scroll up and down with the following actionscript.

[AS]on(release) {
contact_txt.scroll -= 1;
}[/AS]

The code works fine, though I want when I press, the box to keep scrolling. Currently I have to press, press, press, press, to get a small amount down.[/FONT]