Some of the timestamps I saw (I only looked at a few of the files) were as far back as 2001. Linux servers are obviously extremely popular on the Internet nowadays but I can remember "back in the day" when Solaris/SunOS was the popular platform (and, to a lesser extent, the others mentioned) and one of the primary targets. There were lots of exploits for {sendmail, BIND, the NFS server, ...} running on Solaris -- which was a PITA to keep up-to-date.