Page generation with -start crashes with TypeError

What is causing this crash?

>interwiki.py -start:A
Checked for running processes. 1 processes currently running, including the current process.
NOTE: Number of pages queued is 0, trying to add 60 more.
Dump fi (wikipedia) saved
Traceback (most recent call last):
File "C:\svn\pywikipedia\interwiki.py", line 1771, in <module>
bot.run()
File "C:\svn\pywikipedia\interwiki.py", line 1520, in run
self.queryStep()
File "C:\svn\pywikipedia\interwiki.py", line 1494, in queryStep
self.oneQuery()
File "C:\svn\pywikipedia\interwiki.py", line 1462, in oneQuery
site = self.selectQuerySite()
File "C:\svn\pywikipedia\interwiki.py", line 1436, in selectQuerySite
self.generateMore(globalvar.maxquerysize - mycount)
File "C:\svn\pywikipedia\interwiki.py", line 1370, in generateMore
page = self.pageGenerator.next()
File "c:\svn\pywikipedia\pagegenerators.py", line 684, in DuplicateFilterPageGenerator
for page in generator:
File "c:\svn\pywikipedia\pagegenerators.py", line 235, in AllpagesPageGenerator
for page in site.allpages(start = start, namespace = namespace, includeredirects = includeredirects):
File "c:\svn\pywikipedia\wikipedia.py", line 5247, in allpages
for p in soup.api.query.allpages:
TypeError: 'NoneType' object is not iterable

>python version.py
Pywikipedia [http] trunk/pywikipedia (r6015, Oct 24 2008, 18:29:39)
Python 2.5.1 (r251:54863, May 1 2007, 17:47:05) [MSC v.1310 32 bit (Intel)]