extremely has gioven you the correct solution to your problem, but I'd just like to point out that had you been using the -w flag in your code then perl would have pointed out your error to you. For example, running Perl 5.005_03, I get the following:

$ perl -w -e 'my %hash = { one => 1}'
Reference found where even-sized list expected at -e line 1.
$
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--
<http://www.dave.org.uk>

"Perl makes the fun jobs fun
and the boring jobs bearable" - me