This is not a WP issue this is an issue with PHP 5 does not have default support for MySql.
Here are the instructions that worked for me:
The required files from the PHP5 distribution package are... php-ini.dist, php5ts.dll, php_mysql.dll, php_mysqli.dll, libmysql.dll, php-cgi.exe
You may read on the net the need to copy some of these DLLs to the <windows>\system32 directory and or the <Apache2>\bin directory. Neither of these are necessary as long as your php.ini is configured correctly, as it was in my original article.
Secondly, when configuring PHP.ini there is one additional step required. Simply uncomment the (remove the first ;) from the line
As above, all other steps in the "Configuring PHP.ini" section should also be carried out with this single additional step.
That's all that is required, you will now have a working installing of PHP5 and MySQL.