There was a spamming problem on my blog a few months ago. Though I have Akismet to block them, I quickly get bored seeing my spamming box is filled with trashes. It is necessary to include some kinda of verification stuff for the comment module.
Unfortunately, due to my laziness I left an unfinished verification system for months.
Well, the comment function here is no longer disabled. I just implemented Recaptcha 2. K, now please get busy commenting! XD