Troubleshooting frozen object in tzinfo_timezone

[Morten]

Hi. Off and on I get a "can't modify frozen object" when working with
the tzinfo_timezone plugin. I've added some debugging in the code to try
and track down what goes wrong:

def tzinfo
RAILS_DEFAULT_LOGGER.debug("TZINFO STATE '#{@tzinfo}' class
#{@tzinfo.class} frozen? #{@tzinfo.frozen?}")
return @tzinfo if @tzinfo
RAILS_DEFAULT_LOGGER.debug("TZINFO ASSIGN TO #{MAPPING[name]}")
begin
@tzinfo = MAPPING[name]
rescue TypeError => type_error
RAILS_DEFAULT_LOGGER.debug("TZINFO TYPE ERROR #{type_error}")
raise type_error
end
RAILS_DEFAULT_LOGGER.debug("TZINFO ASSIGNED TO #{@tzinfo}")
if String === @tzinfo
@tzinfo = TZInfo::Timezone.get(@tzinfo)
MAPPING[name] = @tzinfo
end
@tzinfo
end


When the error occurs, the following makes it to the log:

TZINFO STATE '' class NilClass frozen? false
TZINFO ASSIGN TO Europe/Amsterdam
TZINFO TYPE ERROR can't modify frozen object

Which means, that @tzinfo is nil, and yet, the line

@tzinfo = MAPPING[name]

Causes a TypeError. MAPPING is a hash. I'm mildly confused. Anyone able
to shed some light on what might be the issue or how to dig further into
the problem?

ruby 1.8.4 (2005-12-24) [x86_64-linux]

Thanks.

Morten