and still it asked me the file. I change only the sha1 to the one for the file with the nulls and i got a request:
GET /uri-res/N2R?urn:sha1:7RLNJM6HFKF74WJTOPDUBVKY5QJUBLDT HTTP/1.1

Why when i change the sha1 to the URN for the real file it doesn't request anything? it doesn't check for validation, so what's wrong?
Again, the only thing i change is the sha1 string - nothing else.