Bertrand Mansion has a recent post to his blog looking at repairing missing functionality in the latest OS X update (Lion) with the intl extension and gettext (not installed by default).

Mac OSX Lion ships with PHP 5.3.6. [...] These are all very good solutions, but since I prefer to travel light and the version in Lion already comes with a lot of useful extensions, I preferred to go with it.

He shows how to update the default Lion PHP install to include some of the things he needed for his development including:

• setting up the php.ini file
• installing PEAR/PECL
• installing the intl extension
• and a hack to get gettext working (renaming a base function)