firestarter-0.9.x (x=1,2) checks the system log for firewall rule violations. These violation messages can be used for monitoring and to adjust your firewall rules. BUT: firestarter assumes your system log to be /var/log/messages (which is the default for syslog). In case you use metalog, by default there is no /var/log/messages. There is a /var/log/everything/current instead. If its impossible to make firestarters path to syslog file configurable, then the ebuild should give a hint how to solve this problem (for instance: create a symbolic link /var/log/messages -> /var/log/everything/current)
The author has indicated that he will be adding log-selecting functionality in the future. For now though, modify ~/.gnome2/firestarter and change the line which defaults to: syslog=/var/log/messages to whatever suits your needs. I'm closing this as WONTFIX because upstream will be providing the functionality and there is an easy work around. Thanks for the bug report Udo.