# The usual stuff. Note that A1 is configured in root not in "some.cat"
log4j.rootCategory=DEBUG, A1
log4j.appender.A1=org.apache.log4j.ConsoleAppender

log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A1.layout.ConversionPattern=%5p [%t] %c - %m%n

# Set the priority of "some.cat" to TRACE (defined in
# org.apache.log4j.xml.examples.XPriority). This will actually have
# the side effect of instanciating a category object having the name
# "some.cat" this will cause a ClassCastException if the category
# object is cast as a MyCategory object.

log4j.category.some.cat=TRACE#org.apache.log4j.xml.examples.XPriority