What are good tools/frameworks for i18n of a php codebase?

Question

I have been looking at a few options for enabling localization and internationalization of a dynamic php application. There appears to be a variety of tools available such a

Answer 1

We've been tinkering withZend_Translate, since we use the Zend Framework anyway. It's very well documented and so far extremly solid.

In the past, I've pretty much used my own home-grown solution mostly. Which involves language files with constants or variables which hold all text parts and are just echo'ed in the view/template later on.

As for gettext, in the past I've heard references about PHP's gettext implementation being faulty, but I can't really back that up nor do I have any references right now.