Another approach is the 'decorate-sort-undecorate pattern' or Guttman-Rosler Transform (GRT), which uses the default lexical sorting of sort for maximum efficiency (even if the comparisons involved are numeric):

>perl -wMstrict -le
"my @unsorted = qw(1-1-2  6-1-2  3-1-4  3-11-4  3-2-4);
 my @sorted =
   map { s{ (\d+) }{ sprintf    '%ld', $1 }xmsge;  $_ }
   sort
   map { s{ (\d+) }{ sprintf '%010ld', $1 }xmsge;  $_ }
   @unsorted
   ;
 print qq{@sorted};
"
1-1-2 3-1-4 3-2-4 3-11-4 6-1-2
[download]

Update: Also: Take a look at Sort::Maker.