The relevant section of Graph's Makefile.PL: 
# Some Debian distributions have a broken List::Util 
# (see rt.cpan.org #9568)
eval 'require Scalar::Util; import Scalar::Util qw(weaken)';
if ($@) {
    die <<__EOF__;
$@
You do not have Scalar::Util::weaken, cannot continue, aborting.
__EOF__
}

[download]
and the referenced bug suggests that this check is to detect a broken List::Util installation. Try reinstalling List::Util manually and see if that helps.

In reply to Re: Graph 0.69 on AIX by randyk
in thread Graph 0.69 on AIX by Anonymous Monk

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