how to use mod_zip of nginx

[btaccel btaccel]

The syntax is a space-separated list of the file checksum (CRC-32),
size (in bytes), location (properly URL-encoded), and file name. The
file location corresponds to a location in your nginx.conf;

 - 428    /foo.txt   My Document1.txt

what is /foo.txt? http://localhost:8000/foo.txt ?
does mod_zip work with x-accel-direct?

i always get  'mod_zip: invalid file list from upstream while sending
to client' error.