TypeError after bad LDAP config

I wasn't paying attention and not even sure what I entered, but I was entering in the webui information for LDAP/SSO.

I get the following when going to the SchoolTool page:

Server Error

An internal server error has occurred. This most likely means that you have found a bug in SchoolTool. Please report it on the issue tracker.

Exception

TypeError: must be string or read-only buffer, not None

Traceback

File "/usr/lib/python2.7/dist-packages/zope/publisher/publish.py", line 129, in publish
  obj = request.traverse(obj)
File "/usr/lib/python2.7/dist-packages/zope/publisher/browser.py", line 540, in traverse
  ob = super(BrowserRequest, self).traverse(obj)
File "/usr/lib/python2.7/dist-packages/zope/publisher/http.py", line 457, in traverse
  ob = super(HTTPRequest, self).traverse(obj)
File "/usr/lib/python2.7/dist-packages/zope/publisher/base.py", line 249, in traverse
  publication.callTraversalHooks(self, obj)
File "/usr/lib/python2.7/dist-packages/zope/app/publication/zopepublication.py", line 137, in callTraversalHooks
  self._maybePlacefullyAuthenticate(request, ob)
File "/usr/lib/python2.7/dist-packages/zope/app/publication/zopepublication.py", line 124, in _maybePlacefullyAuthenticate
  principal = auth.authenticate(request)
File "/usr/lib/python2.7/dist-packages/schooltool/app/security.py", line 221, in authenticate
  return self.authPlugin.authenticate(request)
File "/usr/lib/python2.7/dist-packages/schooltool/ldap/security.py", line 304, in authenticate
  principal = self.getPrincipal('sb.person.' + session['username'])
File "/usr/lib/python2.7/dist-packages/schooltool/ldap/security.py", line 364, in getPrincipal
  results = list(client.find(username))
File "/usr/lib/python2.7/dist-packages/schooltool/ldap/security.py", line 238, in find
  users = self.search(base, scope, filter=filter)
File "/usr/lib/python2.7/dist-packages/schooltool/ldap/security.py", line 149, in search
  self.connect()
File "/usr/lib/python2.7/dist-packages/schooltool/ldap/security.py", line 135, in connect
  new_connection.bind_s(who=dn, cred=password)
File "/usr/lib/python2.7/dist-packages/ldap/ldapobject.py", line 220, in bind_s
  msgid = self.bind(who,cred,method)
File "/usr/lib/python2.7/dist-packages/ldap/ldapobject.py", line 214, in bind
  return self.simple_bind(who,cred)
File "/usr/lib/python2.7/dist-packages/ldap/ldapobject.py", line 200, in simple_bind
  return self._ldap_call(self._l.simple_bind,who,cred,EncodeControlTuples(serverctrls),EncodeControlTuples(clientctrls))
File "/usr/lib/python2.7/dist-packages/ldap/ldapobject.py", line 96, in _ldap_call
  result = func(*args,**kwargs)

Your School - server running SchoolTool 2.1