Hide the Scroll Button in text box

[FreeYiyu]

Can any addon hide the scroll button beside the text box and replace them with some other keys, like PageUp/PageDn or the scroll on the mouse?

It's just a very small change but do make the screen looks better since I am playing under 800*600 resolution due to my poor display card.

I used to find one, but it doesn't work. So anyone here happens to come into that?

Thanks a lot!!!