The horizontal line signifies the period Defensio stopped working and I had to weed out SPAM comments by hand. Interesting enough the number of SPAM comment had increased during this period, as can be seen in the period before and after the outage of the plugin due to a serverconfiguration change. I think the reason for this might be because lots of SPAM comments actually where posted on the blog. With all that exposure spammers might have targeted my blog more frequently than usual (e.g. prior to the outage of Defensio plugin). Defensio has been working great after the last fix, so it makes my life much easier. Thanks for small favours!