Again, which cache folder? If you're talking about Inkscape Preferences > System > User Cache, there's no easy way to do it.
I think there might be a hard way to do it (well, at least it would be hard for me). And I think the explanation how to do it lies in that message thread which I referenced earlier. Although I'm not positive. A lot of that message is confusing to me as well.
If this is the cache folder you want to change (Inkscape Preferences > System > User Cache), can you say why? That might lead us to an easier solution.
If that's the one you want to change, and that referenced message doesn't say how, then someone else will have to explain it for you. I don't know how.