The important part of the error message seems to be:
Request header field is missing ':' separator
I suggest using wireshark to ensure you're posting what you think you are.

Since upload speed is your main concern, I also suggest checking out Furl and the various interfaces to Curl.

In reply to Re: HTTP-POST with IO::Socket -- Header problem by Anonymous Monk
in thread HTTP-POST with IO::Socket -- Header problem by Beavis

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