utf-8 allows you to display symbols from multiple languages on a single page, provided that your users have the necessary fonts to view them installed. The later ArsDigita AOLserver distros have nice support for multiple character sets, including utf-8. There is reasonable documentation here:
http://www.arsdigita.com/asj/multilingual/.
Working with utf-8 requires careful attention to webserver, database, environment variable and (when debugging) terminal settings. I have had success on client sites with Oracle; haven't tried with PG.