Artiss Draft List (formerly Simple Draft List) will display a list of the titles of your posts/pages that have not yet been published.
No, I've paid particular attention to backwards compatibility - if you have set up your blog pre version 2 then the code you used should operate the same. However, you won't be benefitting from caching and various other improved features, so please update your code as soon as you can.
It has been tested and been found valid from PHP 4 upwards.
Please note, however, that the minimum for WordPress is now PHP 5.2.4. Even though this plugin supports a lower version, I am not coding specifically to achieve this - therefore this minimum may change in the future.