Thanks, now it's working! I thought that amavis would already know all the local domains from mysql. Well, it's not a big deal to insert manually the domains that needs to be checked for incoming spam. Now I just have to wait until new spam arrives and gets the score inserted into headers.
Still another little question. I noticed I've also received spam that seems to come from no-reply@facebook.com (that's the sender address), but it definitely doesn't. How do I check if SPF checking is working on my server? Thanks.