Similarly I get the error: 'error' object has no attribute 'code' in the following scenario...

[root@jsefler-onprem-62server ~]# grep proxy /etc/rhsm/rhsm.conf
# an http proxy server to use
proxy_hostname=auto-services.usersys.redhat.com
# port for http proxy server
proxy_port=3128
# user name for authenticating to an http proxy, if needed
proxy_user=redhat
# password for basic http proxy auth, if needed
proxy_password=FOOBAR


[root@jsefler-onprem-62server ~]# subscription-manager redeem --email=proxytester
'error' object has no attribute 'code'



[root@jsefler-onprem-62server ~]# tail -f /var/log/rhsm/rhsm.log

2011-08-22 12:56:32,034 [INFO]  @connection.py:348 - Using certificate authentication: key = /etc/pki/consumer/key.pem, cert = /etc/pki/consumer/cert.pem, ca = /etc/rhsm/ca/, insecure = False
2011-08-22 12:56:32,035 [DEBUG]  @connection.py:188 - Loading CA PEM certificates from: /etc/rhsm/ca/
2011-08-22 12:56:32,035 [DEBUG]  @connection.py:171 - Loading CA certificate: '/etc/rhsm/ca/fakamai-cp1.pem'
2011-08-22 12:56:32,036 [DEBUG]  @connection.py:171 - Loading CA certificate: '/etc/rhsm/ca/jsefler-onprem-62candlepin.pem'
2011-08-22 12:56:32,037 [DEBUG]  @connection.py:171 - Loading CA certificate: '/etc/rhsm/ca/redhat-uep.pem'
2011-08-22 12:56:32,038 [DEBUG]  @connection.py:171 - Loading CA certificate: '/etc/rhsm/ca/candlepin-stage.pem'
2011-08-22 12:56:32,038 [DEBUG]  @connection.py:194 - Using proxy: auto-services.usersys.redhat.com:3128
2011-08-22 12:56:32,039 [DEBUG]  @connection.py:209 - Making request: GET https://jsefler-onprem-62candlepin.usersys.redhat.com:8443/candlepin/
2011-08-22 12:56:32,049 [WARNING]  @connection.py:381 - Error fetching supported resources, this UEPConnection is likely not usable:
2011-08-22 12:56:32,049 [ERROR]  @connection.py:383 - Proxy connection failed: 407
Traceback (most recent call last):
  File "/usr/lib/python2.6/site-packages/rhsm/connection.py", line 374, in _load_supported_resources
    resources_list = self.conn.request_get("/")
  File "/usr/lib/python2.6/site-packages/rhsm/connection.py", line 250, in request_get
    return self._request("GET", method)
  File "/usr/lib/python2.6/site-packages/rhsm/connection.py", line 210, in _request
    conn.request(request_type, handler, body=body, headers=self.headers)
  File "/usr/lib64/python2.6/httplib.py", line 914, in request
    self._send_request(method, url, body, headers)
  File "/usr/lib64/python2.6/httplib.py", line 951, in _send_request
    self.endheaders()
  File "/usr/lib/python2.6/site-packages/rhsm/connection.py", line 105, in endheaders
    httpslib.HTTPSConnection.endheaders(self)
  File "/usr/lib64/python2.6/httplib.py", line 908, in endheaders
    self._send_output()
  File "/usr/lib64/python2.6/httplib.py", line 780, in _send_output
    self.send(msg)
  File "/usr/lib64/python2.6/httplib.py", line 739, in send
    self.connect()
  File "/usr/lib64/python2.6/site-packages/M2Crypto/httpslib.py", line 180, in connect
    raise socket.error, "Proxy connection failed: %d" % code
error: Proxy connection failed: 407
2011-08-22 12:56:32,052 [INFO]  @connection.py:360 - Connection Established: host: jsefler-onprem-62candlepin.usersys.redhat.com, port: 8443, handler: /candlepin
2011-08-22 12:56:32,150 [DEBUG]  @cert_sorter.py:70 - Sorting product and entitlement cert status for: 2011-08-22 12:56:32.150275
2011-08-22 12:56:32,190 [DEBUG]  @cert_sorter.py:91 - Installed product IDs: ['100000000000060', '1000000000000023', '1144', '100000000000011', '100000000000010', '100000000000013', '100000000000012', '100000000000015', '27060', '68', '917571', '1', '37069', '37068', '37080', '37065', '37067', '37060', '37062', '100000000000006', '100000000000007', '100000000000004', '100000000000005', '100000000000002', '100000000000003', '100000000000000', '100000000000001', '100000000000020', '100000000000022', '100000000000009', '100000000000008', '37090', '37070']
2011-08-22 12:56:32,191 [DEBUG]  @cert_sorter.py:81 - valid entitled products: []
2011-08-22 12:56:32,191 [DEBUG]  @cert_sorter.py:82 - expired entitled products: []
2011-08-22 12:56:32,192 [INFO]  @pkgprofile.py:114 - Server does not support packages, skipping profile upload.
2011-08-22 12:56:32,194 [DEBUG]  @connection.py:188 - Loading CA PEM certificates from: /etc/rhsm/ca/
2011-08-22 12:56:32,194 [DEBUG]  @connection.py:171 - Loading CA certificate: '/etc/rhsm/ca/fakamai-cp1.pem'
2011-08-22 12:56:32,195 [DEBUG]  @connection.py:171 - Loading CA certificate: '/etc/rhsm/ca/jsefler-onprem-62candlepin.pem'
2011-08-22 12:56:32,195 [DEBUG]  @connection.py:171 - Loading CA certificate: '/etc/rhsm/ca/redhat-uep.pem'
2011-08-22 12:56:32,196 [DEBUG]  @connection.py:171 - Loading CA certificate: '/etc/rhsm/ca/candlepin-stage.pem'
2011-08-22 12:56:32,197 [DEBUG]  @connection.py:194 - Using proxy: auto-services.usersys.redhat.com:3128
2011-08-22 12:56:32,197 [DEBUG]  @connection.py:209 - Making request: POST https://jsefler-onprem-62candlepin.usersys.redhat.com:8443/candlepin/subscriptions?consumer_uuid=cd3531fc-e76e-4fb3-bd0b-4789863caede&email=proxytester@redhat.com&email_locale=en-us
2011-08-22 12:56:32,224 [ERROR]  @managercli.py:62 - exception caught in subscription-manager
2011-08-22 12:56:32,224 [ERROR]  @managercli.py:63 - 'error' object has no attribute 'code'
Traceback (most recent call last):
  File "/usr/sbin/subscription-manager", line 78, in <module>
    sys.exit(abs(main() or 0))
  File "/usr/sbin/subscription-manager", line 69, in main
    return managercli.CLI().main()
  File "/usr/share/rhsm/subscription_manager/managercli.py", line 1225, in main
    cmd.main()
  File "/usr/share/rhsm/subscription_manager/managercli.py", line 215, in main
    self._do_command()
  File "/usr/share/rhsm/subscription_manager/managercli.py", line 712, in _do_command
    if  200 <= e.code <= 210:
AttributeError: 'error' object has no attribute 'code'

Steps to reproduce, change to a bogus hostname in /etc/rhsm/rhsm.conf. The original gaierror was most likely a result of the candlepin host being unreachable at that time.

Issue in error handling in subscription-manager found, working on a fix.

Fixed in subscription-manager.git: 8157ab1b9c3634cbe71607ca9dc71a1bd4bb15e4

Just had to fix the error handling to properly report non-RestlibExceptions (which don't have a code). 

So to be clear I believe this surfaced because the candlepin server in question was unreachable, which is easy to simulate for verifying: subscription-manager config --server.hostname bogusserver.com

You should now get a proper error message and exception logged.

Moving the bug to verified..

Steps to reproduce :

1)
[root@sachbeta pki]# grep proxy /etc/rhsm/rhsm.conf
# an http proxy server to use
proxy_hostname =auto-services.usersys.redhat.com
# port for http proxy server
proxy_port =3128
# user name for authenticating to an http proxy, if needed
proxy_user =redhat
# password for basic http proxy auth, if needed
proxy_password =FOOBAR

[root@sachbeta pki]# subscription-manager redeem --email=proxytester
Network error, unable to connect to server.
 Please see /var/log/rhsm/rhsm.log for more information.

2)
[root@sachbeta pki]# grep proxy /etc/rhsm/rhsm.conf
# an http proxy server to use
proxy_hostname =FOO
# port for http proxy server
proxy_port =1234
# user name for authenticating to an http proxy, if needed
proxy_user =
# password for basic http proxy auth, if needed
proxy_password =

[root@sachbeta pki]# subscription-manager redeem --email=proxytester --locale=en-us
Network error, unable to connect to server.
 Please see /var/log/rhsm/rhsm.log for more information

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHBA-2011-1695.html