Chainsaw (and potentially other log4j 1.3 clients) have LoggingEvent.getTimeStamp, LoggingEvent.getProperty(Stirng), LoggingEvent.getProperties() etc and other accessors that could be supported on log4j 1.2. Chainsaw and XMLDecoder currently uses LoggingEvent mutators that would require dropping final qualifiers on many member variablesto support on log4j 1.2. Instead of doing that, I've added another LoggingEvent constructor that handles the same use pattern to both log4j 1.2 and log4j 1.3 branches.
log4j 1.3 accessors added to log4j 1.2 branch on rev 528257. LoggingEvent constructor added to log4j 1.3 branch in rev 528258.