Problem with PHP $HTTP_POST_VARS

In my program PhpBibliography, http://phpbibliography.sourceforge.net, see also the announce on this blog, I've always used the same authentication code that had always worked and I never noticed that it was still using the array $HTTP_POST_VARS, instead of $_POST.

As far as I knew they worked the same... well, a user told me he experienced problems in authenticating, and after some time spent on thinking it was due to sessions and cookies we realized it was due to the fact that the form did not pass anything... the $HTTP_POST_VARS was not defined.

Well, also the documentation of PHP 5.0 says that this array may be disabled. Now everything uses $_POST :-)