Characters such as éàè have been replaced by U+FFFD REPLACEMENT CHARACTER in french properties files in tomcat-i18n-fr.jar. So, messages in catalina.out looks like GRAVE: "Servlet.service()" pour la servlet Slave000 a g�n�r� une exception instead of GRAVE: "Servlet.service()" pour la servlet Slave000 a généré une exception
I observe the same issue with 6.0.18 and the 6.0.19 release candidate but I can't reproduce this on my machine. It looks like an issue with the RM's build environment. Investigations continue.
Root cause found and fixed in 6.0.x and trunk. It will be used from 6.0.20 onwards.
*** Bug 47049 has been marked as a duplicate of this bug. ***