At XPages Documentation Wiki initialization (first open) this outputs to Domino log:
26.01.2011 16:07:17 HTTP JVM: log4j:WARN No appenders could be found for logger (com.sun.faces.config.ConfigureListener).
26.01.2011 16:07:17 HTTP JVM: log4j:WARN Please initialize the log4j system properly.
It's not a issue but can be checked & fixed for future releases.