[syslog-ng]Who can help a newbie?

All, As a relative newbie in the world syslog-ng i tried a few things. I am able to split all the information that comes into the logging-server into seperate files. Now i would like to change the config in a way that when a specific message comes in it is written to a file but at the same time triggers a shell script that starts running. Who can help me with this? Regards, Martijn Koopsen