I noticed I had an enourmous amount of spam in my moderation queue.
The plugin I used to protect myself from spam wp-hashcash, seemed to have been mastered by spammers.
A download of the newest version did the trick.
If anyone experiences problems with posting comments, please mail me.
Update I: Seems some spam prevailed even over this version. I’d better get to making my own custom changes to wp-hashcsah.
Update II: I changed the secret codes in the plugin. And I broke it for a while. Either one of those could have resulted in the fortunate (hopefully not temporarilly) stop of spam.
Update III: According to Elliot Back, the creator of hashcash, the spammers bruteforce the secret value. Changing it usually is efficient enough to keep them at bay for a while. He’s working on a newer version which features bigger, thus harder to bruteforce values. I just hope they won’t suck my bandwidth too much.
Update IV: Unfortunately there seems to be a lot of computing power or a hack behind the breaking of the hashcash security -_-, I keep getting spam :-/