How to change image next to Forum names

[Simon]

I have had a look through the Theme we are using, and I cant see how to change the pictures, you know, the ones that indicate if something has been posted in a forum or not.
Would anybody be able to tel me what setting needs to be changed, where to find it, and where to store the pictures that I would like to use?

Edit: The images im reffering to are the "Contains new posts", "Contains no new posts" and "Forum is locked" ones.

[D-Man]

it is under manage themes, then expand the theme you want, there you will see image directory

[DaRK]

HaCKeD