why won't recursive ftp work in this directory?

Question

Python newb...beware!

I am trying to recursively ftp some files. In the script below, I get an error:

Traceback (most recent call last):
  File "dump.py", line 7, in <module>
    for root,dirs,files in recursive:
  File "/usr/local/lib/python2.6/site-packages/ftputil/ftputil.py", line 880, in walk
    if self.path.isdir(self.path.join(top, name)):
  File "/usr/local/lib/python2.6/site-packages/ftputil/ftp_path.py", line 133, in isdir
    path, _exception_for_missing_path=False)
  File "/usr/local/lib/python2.6/site-packages/ftputil/ftputil.py", line 860, in stat
    return self._stat._stat(path, _exception_for_missing_path)
  File "/usr/local/lib/python2.6/site-packages/ftputil/ftp_stat.py", line 624, in _stat
    _exception_for_missing_path)
  File "/usr/local/lib/python2.6/site-packages/ftputil/ftp_stat.py", line 578, in __call_with_parser_retry
    result = method(*args, **kwargs)
  File "/usr/local/lib/python2.6/site-packages/ftputil/ftp_stat.py", line 543, in _real_stat
    lstat_result = self._real_lstat(path, _exception_for_missing_path)
  File "/usr/local/lib/python2.6/site-packages/ftputil/ftp_stat.py", line 502, in _real_lstat
    for stat_result in self._stat_results_from_dir(dirname):
  File "/usr/local/lib/python2.6/site-packages/ftputil/ftp_stat.py", line 419, in _stat_results_from_dir
    lines = self._host_dir(path)
  File "/usr/local/lib/python2.6/site-packages/ftputil/ftp_stat.py", line 411, in _host_dir
    return self._host._dir(path)
  File "/usr/local/lib/python2.6/site-packages/ftputil/ftputil.py", line 811, in _dir
    descend_deeply=True)
  File "/usr/local/lib/python2.6/site-packages/ftputil/ftputil.py", line 578, in _robust_ftp_command
    self.chdir(path)
  File "/usr/local/lib/python2.6/site-packages/ftputil/ftputil.py", line 603, in chdir
    ftp_error._try_with_oserror(self._session.cwd, path)
  File "/usr/local/lib/python2.6/site-packages/ftputil/ftp_error.py", line 146, in _try_with_oserror
    raise PermanentError(*exc.args)
ftputil.ftp_error.PermanentError: 550 /usr/local/web: No such file or directory
Debugging info: ftputil 2.6, Python 2.6.5 (linux2)

Exited: 256

I have no idea what that means. However, when I change the directory to "/path/dir2" it works and prints out "file.txt".

Here's my directory structures:

/path/dir1/another/file.txt # I get the above error with this path
/path/dir2/another/file.txt # this works fine, even though the directories have the same structure

My script: import ftputil

ftp = ftputil.FTPHost('ftp.site.com','user','pass')
recursive = ftp.walk("/path/dir1",topdown=True,onerror=None)
for root,dirs,files in recursive:
 for name in files:
  print name
ftp.close