spam on my blog?!

okay, i was just looking over some postings i had made previously and saw there was a comment on me being dateless and there's cow out there who posted spam in my comment box! i feel kind of... violated and offended in some way, but not really surprise as this is a blog. nothing's sacred these days. hah at least not in the internet. but wooow talking about someone trying to get some SEO or free ad links up!