local doesn't do what you think it does. It doesn't declare a new local variable. It temporarily gives a new value (undef) to a previously existing package variable.

You can pre-declare variables with use vars, our or my. In this case you almost certainly want my.

--
<http://www.dave.org.uk>

"The first rule of Perl club is you do not talk about Perl club."
-- Chip Salzenberg