It was the nginx reversed proxy inbetween that needed a little extra configuration:
http://www.cyberciti.biz/faq/linux-unix-bsd-nginx-413-request-entity-too...
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Problem solved.
It was the nginx reversed proxy inbetween that needed a little extra configuration:
http://www.cyberciti.biz/faq/linux-unix-bsd-nginx-413-request-entity-too...