code: public void trace( String msg, Throwable t )
      {
          if( m_delegate.isTraceEnabled() )
          {
              m_delegate.trace( msg, t );
          }
      }
docs: Log an exception (throwable) at the TRACE level with an
  accompanying message.
  
  @param msg the message accompanying the exception
  @param t   the exception (throwable) to log