Multipart Form-Data problem on Rack 1.1, not on Rack 1.0.1

[joshuamiller <elefantstn@gmail.com>]

Hi all-

Ran into a problem today posting multipart form-data to Rack 1.1
running on Passenger 2.2.11 on Ruby 1.9.1 p378, where request#POST
returns nil.  The problem seems to come from here (line 142 of lib/
rack/request.rb):

      elsif @env["rack.request.form_input"].eql? @env["rack.input"]
        @env["rack.request.form_hash"]

The two env variables on the first line are both set to this,
according to show_exceptions:

#<PhusionPassenger::Utils::RewindableInput:0xccd8854 @io=#<UNIXSocket:
0xccd9408>, @rewindable_io=#<File:/tmp/RackRewindableInput26185-0>,
@unlinked=false>

But there is no env['rack.request.form_hash']

So def params does this...

    def params
      self.GET.update(self.POST)

and it breaks.  The error goes away when I back Rack down to 1.0.1.  I
tried to figure out where form_input and input get set so I could
rewind and see where the difference is, or where form_hash is supposed
to be set, but I'm stumped.