ERROR: zero length field name in format in v6.5.4

[David Touzeau]

Dear
I'm using the latest 6.5.4 version
Python 2.6.6 (r266:84292, Dec 27 2010, 00:02:40)
[GCC 4.4.5] on linux2
Debian 6 i386

and receive this error while sync.

[imap]:   26:59.17 Account sync user at domain.tld connection closed
[imap]:   26:59.17 Account sync user at domain.tld 
_get_untagged_response(BYE) => ['Server logging out']
ERROR: While attempting to sync account 'user at domain.tld'
   zero length field name in format
['  File 
"/usr/local/lib/python2.6/dist-packages/offlineimap/accounts.py", line 
234, in syncrunner\n    self.sync()\n', '  File 
"/usr/local/lib/python2.6/dist-packages/offlineimap/accounts.py", line 
294, in sync\n    remoterepos.sync_folder_structure(localrepos, 
statusrepos)\n', '  File 
"/usr/local/lib/python2.6/dist-packages/offlineimap/repository/Base.py", 
line 184, in sync_folder_structure\n dst_repo.makefolder(src_name_t)\n', 
'  File 
"/usr/local/lib/python2.6/dist-packages/offlineimap/repository/IMAP.py", 
line 347, in makefolder\n    self.ui.makefolder(self, foldername)\n', '  
File "/usr/local/lib/python2.6/dist-packages/offlineimap/ui/UIBase.py", 
line 305, in makefolder\n    prefix, foldername, repo))\n']
*** Finished account 'user at domain.tld' in 0:01
[thread]: Unregister thread 'Account sync user at domain.tld'
ERROR: Exceptions occurred during the run!
ERROR: While attempting to sync account 'user at domain.tld'
   zero length field name in format

Traceback:
   File 
"/usr/local/lib/python2.6/dist-packages/offlineimap/accounts.py", line 
234, in syncrunner
     self.sync()
   File 
"/usr/local/lib/python2.6/dist-packages/offlineimap/accounts.py", line 
294, in sync
     remoterepos.sync_folder_structure(localrepos, statusrepos)
   File 
"/usr/local/lib/python2.6/dist-packages/offlineimap/repository/Base.py", 
line 184, in sync_folder_structure
     dst_repo.makefolder(src_name_t)
   File 
"/usr/local/lib/python2.6/dist-packages/offlineimap/repository/IMAP.py", 
line 347, in makefolder
     self.ui.makefolder(self, foldername)
   File 
"/usr/local/lib/python2.6/dist-packages/offlineimap/ui/UIBase.py", line 
305, in makefolder
     prefix, foldername, repo))

Is there any way to fix it ?