try this one
http://www.wingate.com/downloads/WinGat ... 70-USE.EXEIt supports chunked message bodies from clients. I think that "411 Length required" error came from the server, but it's possible the Transfer-Encoding header was removed with the version you were using.
Chunked uploads are very unusual, and can be very problematic. Only HTTP/1.1 supports chunking, so if a client sends chunked requests to a server, every agent in the path must support chunking or the prior one has to spool the entire upload before presenting it to the HTTP/1.0 agent. Unless you know in advance that the entire path supports chunking, and you don't know how big a file you are uploading is (how likely is that?), then it's generally safer to avoid chunked requests. It also means that decisions can't be made in intermediaries based on the size of the file being uploaded, since you don't know until you read it all how big it will be (as a proxy).
What client software is this?
Regards
Adrien