i am now trying to change the language settings of the wordpress installed .

i just downloaded the file es_ES.mo, and created a directory in wp-include file .and placed the file in wp-includes/language .

modified wp-config as u told with this line define(WPLANG, 'es_ES');

the language is not changed ..

Any valuable suggesions will be appreciated .

you might want to read this post on switching from wp's gettext.php to PHP's gettext. interesting stuff - i hope babelfish does it's job... MarkusW posts in the german wordpress forum, refering to this speed comparison.
regards, erik

Thanks for the suggestions. You are indeed correct about the cookie name - I had it right in my code, but typed it wrong here! I've corrected the article now. Also, that's a good idea for the redirection.

AJAX wouldn't really be suitable for the locale menu. It would mean having to download every localized string, search through the web page, and replace each value. The amount of work involved in this would be enormous, especially considering that a user is probably only going to switch language once.

this gives a nicer user-feel this is what i ended up with & what works fine for me:
// function to redirect
function doredirect($location) {
global $is_IIS;
$location = str_replace( array("\n", "\r"), '', $location);
if ($is_IIS)
header("Refresh: 0;url=$location");
else
header("Location: $location");
}
// end redirect function
if (isset ($_GET['lang']))
{
setcookie ('language', $_GET['lang'], time () 60 * 60 * 24 * 2, '/');
define ('WPLANG', $_GET['lang']);
if ( isset ($_GET['redirect']) )
define('ABSPATH', dirname(__FILE__).'/');
require_once(ABSPATH.'wp-settings.php');
doredirect($_GET['redirect']);
exit;

}
else if (isset ($_COOKIE['language'])) {
define ('WPLANG', $_COOKIE['language']);
if ( isset ($_GET['redirect']) ) {
define('ABSPATH', dirname(__FILE__).'/');
require_once(ABSPATH.'wp-settings.php');
doredirect($_GET['redirect']);
exit;
}
}
else {
define ('WPLANG', '');
}
// wp needs this
define('ABSPATH', dirname(__FILE__).'/');
require_once(ABSPATH.'wp-settings.php');

regards, erik