Comment 2 for bug 1267381

Specifcally, installation fails *even when $http_proxy and/or $https_proxy is configured.

Details:
We have a proxy at 10.32.1.250:8080. It's completely transparent, it simply serves for authentication (log who accesses the internet).

(A) If I do neither configure $http_proxy, nor $http_proxy, I get:

root@ltsp8:~# export http_proxy=
root@ltsp8:~# export https_proxy=
root@ltsp8:~# dropbox start -i
Starting Dropbox...
Dropbox is the easiest way to share and store your files online. Want to learn more? Head to http://www.dropbox.com/

Traceback (most recent call last):
  File "/usr/bin/dropbox", line 1404, in <module>
    ret = main(sys.argv)
  File "/usr/bin/dropbox", line 1393, in main
    result = commands[argv[i]](argv[i+1:])
  File "/usr/bin/dropbox", line 817, in update
    download()
  File "/usr/bin/dropbox", line 540, in download
    download = DownloadState()
  File "/usr/bin/dropbox", line 264, in __init__
    self.size = int(self.socket.info()['content-length'])
  File "/usr/lib/python2.7/rfc822.py", line 388, in __getitem__
    return self.dict[name.lower()]
KeyError: 'content-length'
The installation of Dropbox failed.

(B) If I configure $http_proxy only, I get:

root@ltsp8:~# export http_proxy=http://10.32.1.250:8080
root@ltsp8:~# export https_proxy=
root@ltsp8:~# dropbox start -i
Starting Dropbox...
Dropbox is the easiest way to share and store your files online. Want to learn more? Head to http://www.dropbox.com/

Enter username for Zieladresse ausserhalb des Kepler-Netzwerkes (proxyL) at 10.32.1.250:8080: kup
Enter password for kup in Zieladresse ausserhalb des Kepler-Netzwerkes (proxyL) at 10.32.1.250:8080:

(at this point, installation hangs forever, obviously trying to get through to an https:// address).

(C) If I configure both $http_proxy and $https_proxy, I get:

root@ltsp8:~# export http_proxy=http://10.32.1.250:8080
root@ltsp8:~# export https_proxy=https://10.32.1.250:8080
root@ltsp8:~# dropbox start -i
Starting Dropbox...
Dropbox is the easiest way to share and store your files online. Want to learn more? Head to http://www.dropbox.com/

Enter username for Zieladresse ausserhalb des Kepler-Netzwerkes (proxyL) at 10.32.1.250:8080: kup
Enter password for kup in Zieladresse ausserhalb des Kepler-Netzwerkes (proxyL) at 10.32.1.250:8080:

Error: Trouble connecting to Dropbox servers. Maybe your internet connection is down, or you need to set your http_proxy environment variable.

URL that failed to download: http://www.dropbox.com/download?plat=lnx.x86_64
Error: [Errno 1] _ssl.c:509: error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol
http_proxy = http://10.32.1.250:8080https_proxy = https://10.32.1.250:8080
The installation of Dropbox failed.

So, there's literally no way that works. Dropbox cannot be installed behind a proxy.

Please fix quick!