DW CS3, Spry, Collapsible panels, behaviors

[maguskrool]

Hi.

I'm building a web site in DW CS3, using spry.collapsible panel widgets as menu items. Each menu item then has several sub-menu items on the inside of each panel.

Each main menu item is represented by an image (img1).

What I need:

- Panel closed (img1): onMouseOver, the image should change (img2); onMouseOut, image changes to img1 again;

- Panel open: menu item's image changes to img3; onMouseOver, image changes to img1; onMouseOut, image changes to img3 again;

I think perhaps this could be achieved by changing the .css styles applied, but haven't managed to get results yet.

Can anyone shed some light on this for me? Thanks in advance.