I have a few quesitons about CodeIgniter

[eluser]BrianDHall[/eluser]
For AJAX and Doctrine, check a forum search or poke around in Ignited Code forum or the wiki. I've seen many doctrine threads for its various versions, and for AJAX there may be a few.

On ORM, I highly recommend you checkout Datamapper OverZealous Extension (DMZ) over in Ignited Code. I love it dearly, it's all I've ever wanted in an ORM system and it has a few great extensions that handle arrays and HTML forms most ingeniously.

For Smarty, I recently saw a post around about a Smarty library someone put together to ease use of Smarty in CI, so you might check that out. I just consider Smarty one more system to learn, so I just stick with pure php in my Views.

For internationalization, I'll have to leave that to someone who is more familiar with that - I'm pretty well mono-lingual.