Protect cmssh loader from possible SiteDB outage (originally: does not load)

I'm getting the following error upon loading cmssh:

Loading external/libtiff ... DONE
Loading external/libungif ... DONE

cmssh+pylab Python environment [backend: Agg].

[TerminalIPythonApp] Error in loading extension: cmssh_extension
## Check your config files in /home/joosep/cmssh/soft/.ipython/profile_cmssh

BadStatusLine Traceback (most recent call last)
/home/joosep/cmssh/soft/install/lib/python2.6/site-packages/IPython/core/extensions.pyc in load_extension(self, module_str)
88 if module_str not in sys.modules:
89 with prepended_to_syspath(self.ipython_extension_dir):
---> 90 **import**(module_str)
91 mod = sys.modules[module_str]
92 return self._call_load_ipython_extension(mod)

/home/joosep/cmssh/soft/.ipython/extensions/cmssh_extension.py in ()
25 from cmssh.iprint import PrintManager, print_error, print_warning, print_info
26 from cmssh.debug import DebugManager
---> 27 from cmssh.cms_cmds import dbs_instance, Magic, cms_find, cms_du
28 from cmssh.cms_cmds import cms_ls, cms_cp, verbose, cms_dqueue, cmscrab
29 from cmssh.cms_cmds import cms_rm, cms_rmdir, cms_mkdir, cms_root, cms_xrdcp

/home/joosep/cmssh/soft/cmssh/src/cmssh/cms_cmds.py in ()
21 from cmssh.iprint import msg_red, msg_green, msg_blue
22 from cmssh.iprint import print_warning, print_error, print_status, print_info
---> 23 from cmssh.filemover import copy_lfn, rm_lfn, mkdir, rmdir, list_se, dqueue
24 from cmssh.utils import list_results, check_os, unsupported_linux
25 from cmssh.utils import osparameters, check_voms_proxy, run, user_input

/home/joosep/cmssh/soft/cmssh/src/cmssh/filemover.py in ()
28 from cmssh.utils import PrintProgress, qlxml_parser
29 from cmssh.url_utils import get_data
---> 30 from cmssh.sitedb import SITEDBMGR
31
32 def get_dbs_se(lfn):

/home/joosep/cmssh/soft/cmssh/src/cmssh/sitedb.py in ()
74
75 # Singleton
---> 76 SITEDBMGR = SiteDBManager()

/home/joosep/cmssh/soft/cmssh/src/cmssh/sitedb.py in **init**(self, url, threshold)
47 self.timestamp = time.time()
48 self.threshold = threshold # in sec, default 3 hours
---> 49 self.init()
50
51 def init(self):

/home/joosep/cmssh/soft/cmssh/src/cmssh/sitedb.py in init(self)
54 url = self.url + '/site-names'
55 names = {}
---> 56 with get_data_and_close(url) as data:
57 for row in parser(data.read()):
58 names[row['site_name']] = row['alias']

/opt/software/cms/slc5_amd64_gcc462/external/python/2.6.4/lib/python2.6/contextlib.pyc in **enter**(self)
14 def **enter**(self):
15 try:
---> 16 return self.gen.next()
17 except StopIteration:
18 raise RuntimeError("generator didn't yield")

/home/joosep/cmssh/soft/cmssh/src/cmssh/url_utils.pyc in get_data_and_close(url, headers)
161 opener = urllib2.build_opener(handler)
162 urllib2.install_opener(opener)
--> 163 data = urllib2.urlopen(req)
164 try:
165 yield data

/opt/software/cms/slc5_amd64_gcc462/external/python/2.6.4/lib/python2.6/urllib2.pyc in urlopen(url, data, timeout)
122 if _opener is None:
123 _opener = build_opener()
--> 124 return _opener.open(url, data, timeout)
125
126 def install_opener(opener):

/opt/software/cms/slc5_amd64_gcc462/external/python/2.6.4/lib/python2.6/urllib2.pyc in open(self, fullurl, data, timeout)
387 req = meth(req)
388
--> 389 response = self._open(req, data)
390
391 # post-process response

/opt/software/cms/slc5_amd64_gcc462/external/python/2.6.4/lib/python2.6/urllib2.pyc in _open(self, req, data)
405 protocol = req.get_type()
406 result = self._call_chain(self.handle_open, protocol, protocol +
--> 407 '_open', req)
408 if result:
409 return result

/opt/software/cms/slc5_amd64_gcc462/external/python/2.6.4/lib/python2.6/urllib2.pyc in _call_chain(self, chain, kind, meth_name, _args)
365 func = getattr(handler, meth_name)
366
--> 367 result = func(_args)
368 if result is not None:
369 return result

/home/joosep/cmssh/soft/cmssh/src/cmssh/url_utils.pyc in https_open(self, req)
41 # a reference to a function which, for all intents and purposes,
42 # will behave as a constructor
---> 43 return self.do_open(self.get_connection, req)
44
45 def get_connection(self, host, timeout=300):

/opt/software/cms/slc5_amd64_gcc462/external/python/2.6.4/lib/python2.6/urllib2.pyc in do_open(self, http_class, req)
1117 try:
1118 h.request(req.get_method(), req.get_selector(), req.data, headers)
-> 1119 r = h.getresponse()
1120 except socket.error, err: # XXX what error?
1121 raise URLError(err)

/opt/software/cms/slc5_amd64_gcc462/external/python/2.6.4/lib/python2.6/httplib.pyc in getresponse(self)
972 method=self._method)
973
--> 974 response.begin()
975 assert response.will_close != _UNKNOWN
976 self.__state = _CS_IDLE

/opt/software/cms/slc5_amd64_gcc462/external/python/2.6.4/lib/python2.6/httplib.pyc in begin(self)
389 # read until we get a non-100 response
390 while True:
--> 391 version, status, reason = self._read_status()
392 if status != CONTINUE:
393 break

/opt/software/cms/slc5_amd64_gcc462/external/python/2.6.4/lib/python2.6/httplib.pyc in _read_status(self)
353 # Presumably, the server closed the connection before
354 # sending a valid response.
--> 355 raise BadStatusLine(line)
356 try:
357 [version, status, reason] = line.split(None, 2)

BadStatusLine: