Using JRun
If you are using the default instance of JRun, and using a separate web server (e.g. not JRun's own web server), the properties file is in a directory within your JRun install directory called jsm-default/services/jse/properties. The file is called servlet.properties, and lines must be added for each servlet, for example:
servlet.Login.code=com.jcorporate.expresso.core.servlet.
In addition, the DefaultInit servlet must be pointed to your configuration directory:
servlet.DefaultInit.args=configDir=/usr/web/config
Of course, you would substitute the appropriate directory for the "/usr/web/config" value.