sub sect
{
 my @a = split /\./, $a;
 my @b = split /\./, $b;
 
 my $len = @b;
 if ( @a > @b )
 {
  $len = @a;
 }
 
 foreach my $i ( 0 .. $len-1 )
 {
  if ( $a[$i] > $b[$i] )
  {
   return 1;
  }
  elsif ( $a[$i] < $b[$i])
  {
   return -1;
  }
 }
 return 0;
}

my @s = ( "1.0", "3", "2.0.1", "4.1.1.1", "1.0.1", "1.1", "1.0.2", "2.0" );

my @t = sort sect @s;

print "@t\n";
__DATA__
1.0 1.0.1 1.0.2 1.1 2.0 2.0.1 3 4.1.1.1