I tried migration from 0.3.0 to the current cvs version.
I used the classic template and never edited dbinit.py,
so I simply copied roundup/templates/classic/dbinit.py
to a copy of the 0.3.0 instance.

Now the following problem occurs:

ratbert:/Projects/psp/roundup/cvs
$ PYTHONPATH=. ./roundup-admin -i ../unstable/tool-issues list user
Traceback (most recent call last):
  File "./roundup-admin", line 30, in ?
    sys.exit(tool.main())
  File "roundup/admin.py", line 987, in main
    ret = self.run_command(args)
  File "roundup/admin.py", line 912, in run_command
    self.db = instance.open('admin')
AttributeError: '_roundup_instance_1' module has no attribute 'open'

As soon as I uncomment the new lines in 
IssueClass, then it works again:

class IssueClass(roundupdb.IssueClass):
    ''' issues need the email information
    '''
#    INSTANCE_NAME = instance_config.INSTANCE_NAME
    ISSUE_TRACKER_WEB = instance_config.ISSUE_TRACKER_WEB
    ISSUE_TRACKER_EMAIL = instance_config.ISSUE_TRACKER_EMAIL
    ADMIN_EMAIL = instance_config.ADMIN_EMAIL
    MAILHOST = instance_config.MAILHOST
    MESSAGES_TO_AUTHOR = instance_config.MESSAGES_TO_AUTHOR
#    EMAIL_SIGNATURE_POSITION = instance_config.EMAIL_SIGNATURE_POSITION

Enabling either of the two lines causes the failure.

I have a localconfig with

EMAIL_SIGNATURE_POSITION = 'bottom'
INSTANCE_NAME = 'tool-issues'

but this doesn't seem to affect the problem,
I can remove these settings and with the lines
above enabled still get the same error.

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Removing these lines isn't the solution to the problem;
I was only hoping that it might help to locate the problem.
In fact, the mail gateway really needs the instance name
and does not work without it.

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[richard here - not logged in]
Do you get the same problem with a fresh 0.4 instance?

I just simulated the same setup - having a localconfig 
with those two variables - and it worked OK. I guess we 
need to figure why the open function isn't being imported.

Can you put some debugging in the instance __init__ and 
try to see what's going on there?

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user_id=416927

Putting

EMAIL_SIGNATURE_POSITION = 'bottom'
INSTANCE_NAME = 'Roundup issue tracker'

into my instance_config.py solves the problem,
so it seems that importing localconfig did not
work. Where do I have to place this file? Putting
it into the same directory as instance_config.py
did not work, as a

try:
    from localconfig import *
except ImportError:
    localconfig = None
print localconfig

shows - localconfig is None.

Anyway, this is a different problem, and most
likely a user error.

After removing the try/except around import dbinit
(as suggested on the roundup list) reveals the real
problem:

Traceback (most recent call last):
  File "./roundup-admin", line 30, in ?
    sys.exit(tool.main())
  File "roundup/admin.py", line 987, in main
    ret = self.run_command(args)
  File "roundup/admin.py", line 904, in run_command
    instance = roundup.instance.open(self.instance_home)
  File "./roundup/instance.py", line 47, in open
    return imp.load_package(modname, instance_home)
  File "../unstable/tool-issues/__init__.py", line 22, in ?
    from dbinit import *
  File "../unstable/tool-issues/dbinit.py", line 35, in ?
    class IssueClass(roundupdb.IssueClass):
  File "../unstable/tool-issues/dbinit.py", line 38, in IssueClass
    INSTANCE_NAME = instance_config.INSTANCE_NAME
AttributeError: '_roundup_instance_1.instance_config' module has no attribute 'INSTANCE_NAME'

Logged In: YES 
user_id=416927

Putting EMAIL_SIGNATURE_POSITION and 
INSTANCE_NAME into the instance's instance_config.py
instead of localconfig works - this is now correctly
mentioned in the MIGRATION.txt, so I close this bug.