ModLogAn is a modular logfile analyzer which is able to generate reports based on 15 different inputformat from variuos sections (http, ftp, mail, firewall, isdn, ...). As a special feature it can combine multiple inputfiles from clustered servers.
Modlogan is DISCONTINUED. See the homepage. I used to be a contributor, and it was a really good software at that time. But the web has changed a lot, and log file analysis is no longer what it used to be in 2000. You probably want to use a more modern software now, with a fancy Web 2.0 user interface. This is not a bug of modlogan; just a result of it being discontinued for several years now.