Any idea about this event in splunkd.log?
02-17-2014 17:36:12.384 +0000 WARN LMTracker - skipping directive, reason='found invalid directive cmd='D_set_active_group' args=[Enterprise,,] argsize=3'
Are you connecting a <= 5.x license slave to a >= 6.x master? It would appear that this message is to be expected in this scenario due to a differing argument count/differing capabilities. This can be safely ignored, or the logging level of the LMTracker category can be set above WARN to avoid logging the condition.