Net::HTTP does not allow users to handle Content-Encoding in responses like 1.x
I added a feature to always add a feature to always add Accept-Encoding to HTTP requests and always decode HTTP responses with Content-Encoding.
On Ruby 1.9 and older you could handle Content-Encoding for yourself.
Now Ruby always handles Content-Encoding for you, but does not give you a good indicator that this has taken place. In mechanize this leads to an incompatibility as the Content-Length header is not updated from the original value.
This also disallows handling of bad server responses that browsers handle.
The attached patch (upcoming) addresses this by only handling Content-Decoding in a response if the user did not override the Accept-Encoding header.
Since this is an incompatibility I would like this fixed for Ruby 2.0. Sorry I did not catch it sooner, I was too busy with RubyGems and RDoc.