expanded menus

Hi, just trying out expanding menus. I have downloaded expanding-single.js then renamed it udm-custom.js
Created a menu and it all appears to be working fine. but i can't see the down arrow to show there are entries below. There does appear to be a faint white vertical line. This when i use IE 6.0 If i use Firefox 2.0 there appears a very small dot, but not the down arrow. I do have down-green.gif and down-red.gif

Any suggestions. I don't need to recreate udm-style.js do i.

Thanks