Hanging on auth error...

[PSyton]

I have a crash log for situation with auth error on SMTP server. After this event I saw infinity hang. Looks like that lockfile didn't free.I had to kill process and to delete lockfile by hands.
Traceback (most recent call last):
File "manage.py", line 11, in
execute_manager(settings)
File "/usr/lib/python2.6/site-packages/django/core/management/init.py", line 438, in execute_manager
utility.execute()
File "/usr/lib/python2.6/site-packages/django/core/management/init.py", line 379, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/usr/lib/python2.6/site-packages/django/core/management/base.py", line 191, in run_from_argv
self.execute(_args, *_options.dict)
File "/usr/lib/python2.6/site-packages/django/core/management/base.py", line 220, in execute
output = self.handle(_args, *_options)
File "/usr/lib/python2.6/site-packages/django/core/management/base.py", line 351, in handle
return self.handle_noargs(**options)
File "/usr/lib/python2.6/site-packages/django_mailer/management/commands/send_mail.py", line 47, in handle_noargs
send_all(block_size, backend=settings.USE_BACKEND)
File "/usr/lib/python2.6/site-packages/django_mailer/engine.py", line 87, in send_all
connection.open()
File "/usr/lib/python2.6/site-packages/django/core/mail/backends/smtp.py", line 48, in open
self.connection.login(self.username, self.password)
File "/usr/lib/python2.6/smtplib.py", line 589, in login
raise SMTPAuthenticationError(code, resp)
smtplib.SMTPAuthenticationError: (454, '4.7.0 Cannot authenticate due to temporary system problem. Try again later. q53sm52029eeh.4')