Logstash.log gets flooded?

Hi All,
Can't understand why logstash suddenly writes all input to logstash.log?
Is that some new feature in logstash 1.5?

My output config look like this:
output {
elasticsearch {
host => "X.X.X.X"
port => "9200"
protocol => "http"
cluster => "elastic-XXX-cluster"

I haven't seen this behavior before?
Any idea how to turn this off?


Get rid of that!

That one is of course comment out already (got lost in formatting).


Ah, got hit by the following issue, that's what's filling my logs:
elasticsearch output - failed with response of 400