Delete spam posts

Hi,

I have been researching for a week how to get rid of horrible spam that is all around my forum.

I found very nice tools developed by keydog, grez, dimkalinux and others

fancy-stop-spam
extension-release-stopforumspamcom-antispam
extension-url-checker
extension-akismet-by-garciat-rich-pedley-grez

If I´m not missing something, those are made for not letting bots register or send spam to your forums. But what about deleting previous post.

I got rid of bots with no posts, but the ones with one o more post are still there.

I tried url_cheker but I´m getting this error.
Fatal error: Call to undefined function parse_signature() in /home/foros/public_html/punbb-1.4.1/sfs.php on line 94

Are there any other ways to deal with previous spam posts?

Any help would be appreciated
Muchas gracias