Deprecated - Database compatibility

In the Control Panel of our VPS appears:

Important Notice: Incompatible versions of Mysql 4.0.x and NPTL based systems.

If you are running a newer linux system which is NPTL based (CentOS 4, Fedora 3+, RHE 4, etc) and are having problems with MySQL 4.0.x (versions later then 4.0.23*), we recommend upgrading to MySQL 4.1.x as we have determined that there are compatibility issues on these platforms. You can easily upgrade to 4.1.x by changing the Mysql Version in Tweak Settings

Hi. I have three simple PHP document management pages (create.php, upload.php and display.php). Each page calls an additional PHP page and share include files for opening and closing the SQL database that stores the documents. How can I port this into a drupal module (I am a drupal novice that has just read the module development tutorial). I would just have the Drupal page point to the PHP pages, however I'd like to integrate it as a module in Drupal to leverage Drupal's Security.

Would like to have multiple sites with common usersnames from one database but completely different content.

I have a client that loves drupal and would like to have quite a few sites that can be selected by a dropdown menu at the top of the page. When anyone selects the different site or location to be more exact. The different location will have completely different content, with the exception of the usernames and passwords.

Can i communicate Oracle 9i and Drupal? Thanks.

I am setting up a system where I would like to grab the user and groups information from a mysql database but would like to use postgresql for all the nodes and comments.

Is there a way to configure drupal to do this?

I'm a newbie with Drupal (4.7RC3) but have been using php and postgres for a long time. My first page creation gave me this: