software localization with PHP

Hi all, I have a question about localizing PHP scripts. I understand that for basic localization one can have a "strings" file for each language, which contains string variables and values such as: <?php $title = "Welcome!"; $error = "An error occurred."; ?> Then, in the scripts just "include" the language file at the beginning and simply call the strings by their variable names. The issue I have is when embedding variables within these strings. Suppose I need to call the user by his/her first name, in the strings file I would have a variable like this: $greeting = "Welcome! $first_name"; The problem is, the strings file is loaded at the beginning of the script before $first_name was set, so the $greeting string will come out as "Welcome! ", with $first_name being an empty string. Even if I loaded the strings file after the $first_name variable is set, the problem still remains - when $first_name variable is changed, the strings file has to be reloaded. What is the best way of dealing with this problem? Is there a place to find "best practices" on localizing PHP software? Tao