James Miller has posted a working configuration some time ago on the D
newsgroup:
http://forum.dlang.org/thread/mgoveqnyimerdazvjqgb@forum.dlang.org
I think the main issue is that nginx 1.0.x does not support HTTP/1.1 for
its reverse proxy but vibe.d often needs it for chunked transfers. The
thing with "proxysetheader Content-Length $bodybytessent;"
sounds like a bug though and I will look into it.
Regards