In case of a discovery failure now also the stacktrace of the cause will be added to the diagnostic message. Jdk14Logger now correctly uses the specified logger name. Change scope of Jdk14Logger.log(Level, String, Throwable) to protected, allowing subclasses to modify the logging output. Properly synchronize access to protected static field LogFactory.nullClassLoaderFactory. Prevent potential deadlock scenario in WeakHashtable. Potential missing privileged block for class loader. LogFactoryImpl.setAttribute - possible NPE. Log4JLogger uses deprecated static members of Priority such as INFO. Static analysis suggests a number of potential improvements. SimpleLog.log - unsafe update of shortLogName. LogFactory.diagnosticPrefix and diagnosticsStream could be final.