It’s a shame that, although PHP’s old Mysql PDO driver is currently deprecated and replaced with MysqlND, some well-known PHP frameworks, specially for mail management in Unix/Linux, like squirrelmail, Horde, Roundcube…have yet to update to the new driver.
This is specially annoying with dependency-driven package systems like Debian where -unless you want to spend hours compiling and configuring the mysql server- you have to choose between Mysql and MysqlND drivers. If you happen to use the PHP Mysqli methods -and you should as they are more modern, efficient and powerful-, you would probably have installed MysqlND instead of the old Mysql-PDO. This can be an annoyance when you need to install a framework using the old drivers, like the above mentioned mail front-ends. This was the case when I installed Roundcube in one of my Linux servers, and I found that the password plugin (that allows the users to change their passwords) only supported the old drivers.
So I decided to implement a new driver that would use the MysqlND driver and the mysqli methods. You can download it from my github repository. The driver is compatible with the last stable version available for Debian, concretely Roundcube v7.x. Installation is pretty straightforward, and instructions are specified in the README.md file. Hope it can save you some hours of work.