AttributeError: 'NoneType' object has no attribute 'next'

[caperoni]

Here is a bug when --crawl=3 is enabled

thread 1: 'AttributeError: AttributeError: 'NoneType' object has no attribute 'next''
Traceback (most recent call last):
  File "/root/sqlmap-dev/lib/core/threads.py", line 96, in exceptionHandledFunction
    threadFunction()
  File "/root/sqlmap-dev/lib/utils/crawler.py", line 104, in crawlThread
    href = tag.get("href") if hasattr(tag, "get") else tag.group("href")
  File "/root/sqlmap-dev/thirdparty/beautifulsoup/beautifulsoup.py", line 610, in get
    return self._getAttrMap().get(key, default)
  File "/root/sqlmap-dev/thirdparty/beautifulsoup/beautifulsoup.py", line 884, in _getAttrMap
    if not getattr(self, 'attrMap'):
  File "/root/sqlmap-dev/thirdparty/beautifulsoup/beautifulsoup.py", line 682, in __getattr__
    return self.find(tag)
  File "/root/sqlmap-dev/thirdparty/beautifulsoup/beautifulsoup.py", line 846, in find
    l = self.findAll(name, attrs, recursive, text, 1, **kwargs)
  File "/root/sqlmap-dev/thirdparty/beautifulsoup/beautifulsoup.py", line 866, in findAll
    return self._findAll(name, attrs, text, limit, generator, **kwargs)
  File "/root/sqlmap-dev/thirdparty/beautifulsoup/beautifulsoup.py", line 392, in _findAll
    i = next(g)
  File "/root/sqlmap-dev/thirdparty/beautifulsoup/beautifulsoup.py", line 902, in recursiveChildGenerator
    current = current.next
AttributeError: 'NoneType' object has no attribute 'next'