I'm switching all of my personal projects over to an EC2 instance running Ubuntu 10.10. Part of the "fun" (Sarcastic quote marks! Yay!) in making the switch is discovering all the software that you were taking for granted and need to reinstall manually. Today I installed SQLite3 but didn't realize I needed to install the PDO driver to get it working in PHP.
Fixing this was actually really simple, but because it wasn't immediately obvious to me, I'm going to assume it isn't immediately obvious to someone else out there.
Here's what you do:
sudo apt-get install php5-sqlite sudo apache2ctl restart
Boom. Now when you run
phpinfo() you should see mysql, sqlite and sqlite2 listed as PDO drivers. The driver simply labeled sqlite is actually the sqlite3 driver.
There you go!