try using Sort::Key, it always performs stable sorts: 
use Sort::Key qw(ikeysort);

my @ordered = ikeysort { $_->{pos} } @unordered;
my @result = ikeysort { $_->{val} } @unordered;

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In reply to Re: Is sorting different in Perl 5.6.1 than in Perl 5.8.8? by salva
in thread Is sorting different in Perl 5.6.1 than in Perl 5.8.8? by frostman

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