And a Chinese startup cracked NewRelic to raise over $10m http://www.v2ex.com/t/125736 It is in Chinese. Code diff is in the comments. It seems they cracks New Relic's Node.js, Python and Java agents, and raised RMB 70m ($10m+) from Matrix and Chengwei (sounds like a Chinese fund): http://source.chinaventure.com.cn/show_2_0_19158.html.
According to the comments from their developer, Python code is written to follow NewsRelic and Java, Ruby, PHP and others are totally written on their own. Apparently they know NewsRelic developers, but they don't have their source code.