FluentdAppender does not properly handle MDC

[AixNPanes]

The following code:

for (String mdcKey : mdcKeys.split(","))
{
  Object value = event.getMDC(mdcKey);
  if (value != null)
  {
    data.put(mdcKey, value);
  }
}

can be replaced by

for(Map.Entry<String, Object> entry:((Hashtable<String, Object>)MDC.getContext()).entrySet())
{
    if (entry.getValue() != null)
        data.put(entry.getKey(), entry.getValue());
}

This seems to fix the problem for me, although it may not be efficient.