I'm not sure exactly when our was introduced, but you can use vars; instead to do the same thing. Example:

use vars qw(@ISA @Export);

@ISA        = qw(Exporter);
@Export     = qw(   error,
                        ff_error,
                        HTMLErrorFormat,
                    );
[download]

vars is basically deprecated in favor of our, but it's still there if you need it.

Update: Forgot to mention that you don't need those commas in your qw() statements. The idea behind qw() is that it splits the list on whitespace, not commas.

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I wanted to explore how Perl's closures can be manipulated, and ended up creating an object system by accident.
-- Schemer

Note: All code is untested, unless otherwise stated