We've decided to release Smarty plugins that make life with Smarty and I18N easy (well, at least as easy as I18N can be per se).

Wolfram Schlich posted a nice overview of best practices to internationalize Smarty templates. His overview can be read in this mailinglist archive.

Unfortunately none of the provided best practices seemed to be compliant to the standard GNU I18N library gettext, as employed in many applications. Hence we thought about implementing our own, which turned out to be both - incredibly easy and very handy.