bzr crashes if FTP server closes connection

I use an FTP account on free hosting for storing my Bazaar repository.

I get bzr crashed if this FTP server closes connection for some reason:

$ bzr up
FTP <email address hidden> password:
FTP control connection closed. Trying to reopen.
FTP <email address hidden> password:
bzr: ERROR: exceptions.EOFError:

Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 920, in exception_to_return_code
    return the_callable(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 1131, in run_bzr
    ret = run(*run_argv)
....
  File "/usr/lib/python2.7/ftplib.py", line 196, in getmultiline
    line = self.getline()
  File "/usr/lib/python2.7/ftplib.py", line 186, in getline
    if not line: raise EOFError
EOFError

Here is FTP session if I try to use 'ftp' command line client:

$ ftp ftp.nm.ru
Connected to ftp.nm.ru.
220 ProFTPD 1.3.3 Server (Pochta.ru FTP Server) [80.68.248.91]
Name (ftp.nm.ru:alex): sashnov
331 Password required for sashnov
Password:
421 Service not available, remote server has closed connection
Login failed.
No control connection for command: No such file or directory
ftp> ls

Expected result:
bzr should show this 421 error message instead of crash.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: bzr 2.5.1-0ubuntu2
ProcVersionSignature: Ubuntu 3.2.0-74.109-generic 3.2.64
Uname: Linux 3.2.0-74-generic x86_64
NonfreeKernelModules: bc_twofish bc_rijn bc_idea bc_gost bc_des bc_cast bc_blowfish bc_bf448 bc_bf128 bc_3des bestcrypt nvidia
ApportVersion: 2.0.1-0ubuntu17.8
Architecture: amd64
Date: Mon Jan 5 11:37:29 2015
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425)
MarkForUpload: True
PackageArchitecture: all
ProcEnviron:
 TERM=xterm
 SHELL=/bin/bash
 PATH=(custom, user)
 LANG=en_US.UTF-8
 LANGUAGE=en_US:en
SourcePackage: bzr
UpgradeStatus: No upgrade log present (probably fresh install)