HTTP 1.1
http://www.w3.org/Protocols/rfc2616/rfc2616.txt

and there is no 405 error, at least not according to this
From the link you posted: "This is a historic document and is not accurate anymore. For up-to-date details on the HTTP specification, see the latest HTTP/1.1 drafts "

The 405 error means the server's not accepting the HTTP POST, which seems like a web server config problem than a programming problem to me...