It works fine for me ( perl, v5.8.3 built for MSWin32-x86-multi-thread): 
>perl -MData::Dumper -we "my $v={''=>undef}; my $h; %$h=%$v; print Dum
+per $h"
--OUTPUT--
$VAR1 = {
          '' => undef
        };

[download]
The code "%{$HashData} = undef;" is incorrect, and not doing anything anyway.

    ...each is assigned his own private delusion but he cannot see the baggage on his own back.

In reply to Re: Problems With Hash Pointer Assignments by NetWallah
in thread Problems With Hash Pointer Assignments by EchoAngel

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