I'm storing date in mySQL table in 0000-00-00 00:00:00 format. Using PHP, I retrieve it in the Sunday, 18 June 2006 format using DATE_FORMAT(dates, '%W, %d %M %Y')
Now I need to display it in English, French and German. Have anyone got any idea how to do it ?

You can do this with strftime() and changing the locale settings. You set the locale to something like de_DE for german and then strftime will spit out Montag, Freitag instead of Monday, Friday.
The PHP manual has the details and some examples here:
http://www.php.net/manual/en/function.strftime.php