Permalink problem – avoid “category” – plugin?

Hi
Is there some way to avoid “category” as a part of my posts’ permalinks?
I’ve set up the permalink structure like this:
/%category%/%postname%/
but instead of getting urls like domain/toscana/siena (where toscana is the category and siena the post) I get this url: domain/category/toscana/siena
I remember seeing in the codex that this is how it works, but is there some way around?
A plugin maybe?
Thanks,
Kjetil