Version 1.0, works with Logstash 1.3.3 and 1.4.1+
Tested and running in production environments w/ logstash v.1.3.3 and v1.4.1+ (NOT 1.5.x!)
This does NOT work with Logstash 1.4.0 due to a bug, nor does it completely work with 1.5.x due to a regex multiline difference in this release: https://discuss.elastic.co/t/logstash-1-5-x-grok-regex-multiline-behavior-change/34347