There is one way I can think about doing it now, that would be somthing like this

open(FILE, "blah");
while (<FILE>) {
      chomp;
      push @array,$_;
}

for( my $i; $i < @array; $i++) {
      ($id,$title,$description) = split(/\|/, $array[$i]);
       if ($id = "THE ID THAT YOU WANT TO UPDATE") {
               splice(@array, $i, 1);
               push @array, "$newid|$newtitle|$newdescription";
        }
}
[download]

then just write your array out into a file
I didnt test this out, so its sorta psuedo-code

-mark