[mandingo]

It's default in vb4,it's a bit confusing though:
admincp>forums and moderators>forum manager>Whatever forum>Edit forum>"go">Style Options>Prefix for Forum Status Images
Now,make sure you either have a different set of icons already made or make them yourself.

Then.rename them all as such:
say for your default icon,the name is :
forum_old-48.png
rename the replacement one with a "prefix" say:
a_
So it would be:
a_forum_old-48.png
Do that with each and every icon.
Upload those to your statusicon folder that you have designated in stylevars
default is images/statusicon

in the Prefix for Forum Status Images just put a_ in there and everything should be all set.