There is a discussion about clarifying how BIP70 signs payment requests
here:
  https://github.com/bitcoin/bips/pull/41

The issue is what to do with the signature field before signing. The code
Mike and I initially wrote does this:

    request.set_signature(string(""));

(sets signature to the empty string)

I think that is a mistake; it should be:

   request.clear_signature();

(clears signature field, so it is not serialized at all).

So: if you are implementing, or have implemented, the payment protocol,
please chime in. I'd like to change the spec and the reference
implementation NOW, while BIP70 is still a 'Draft'.

Because this type of "hey, I'm implementing your standard and it doesn't
work the way I think it should" mistake is exactly why BIPs take a while
before being declared 'Final.'


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Gavin Andresen