Antispam for pblog

I have been getting so many spam comments, I’ve decided to spend few minutes adding antispam support for pblog. I suspect that the spammers will manage to bypass the very simple protection I’ve built but it’ll do for now.

Please let me know if you encounter any problems. If you don’t type the numbers in the given string, pblog will not accept your comment and will fail silently.

I am planning to reimplement some aspects of pblog so I can play with microformats, ASP.NET AJAX, WPF/E, etc. I will revisit the antispam functionality then.