I've just pushed poster 0.7.0 to the cheeseshop. Thanks again to everybody who sent in bug reports, and for letting me know how you're using poster! It's really great to hear from users. poster 0.7.0 fixes a few problems with 0.6.0, most notably:

• Added callback parameters to MutipartParam and multipart_encode so you can add progress indicators to your applications. Thanks to Ludvig Ericson for the suggestion.
• Fixed a bug where posting to a url that returned a 401 code would hang. Thanks to Patrick Guido and Andreas Loupasakis for the bug reports.
• MultipartParam.from_params will now accept MultipartParam instances as the values of a dict object passed in. The parameter name must match the key corresponding to the parameter in the dict. Thanks to Matthew King for the suggestion.
• poster now works under python2.7

poster 0.7.0 can be downloaded from the cheeseshop, or from my website. Documentation can be found at https://atlee.ca/software/poster/ I'm planning on looking at python 3 compatibility soon. Also, if anybody has suggestions on a reliable way to test the streaming http code, I'm open to suggestions! My current methods result in intermittent failures because of the test harness I suspect. poster's code is now available on bitbucket.