@sorted = 
  map {$_->[0], ", "}
  sort { $a->[0] <=> $b->[0]}
  map {[$_, pack ("N*", $_)]}
@unsorted;

##</code><code>##

@unsorted = qw(2 1.2a 2.2 1.2 1.1a);
## A fixed version:
@sorted = 
  map {$_->[0], ", "}
  sort { $a->[1] <=> $b->[1]}
  map {[$_, pack ("N*", $_)]}
@unsorted;

print @sorted, "\n";
## produces:
1.2a, 1.1a, 1.2, 2, 2.2