Index: wp-admin/includes/plugin.php
===================================================================
--- wp-admin/includes/plugin.php	(revision 16578)
+++ wp-admin/includes/plugin.php	(working copy)
@@ -336,6 +336,7 @@
 function get_dropins() {
 	$dropins = array();
 	$plugin_files = array();
+	$language_files = array();
 
 	$_dropins = _get_dropins();
 
@@ -350,7 +351,19 @@
 	}
 
 	@closedir( $plugins_dir );
+	
+	// More advanced plugins for language localization exist in the wp-content/languages directory
+	if ( $language_plugins_dir = @ opendir( WP_CONTENT_DIR . '/languages' ) ) {
+		$locale = get_locale();
+		while ( ( $file = readdir( $language_plugins_dir ) ) !== false ) {
+			if ( (substr( $file, -4 ) == '.php')&&(substr( $file, 0, -4 ) == $locale)) {
+				$language_files[] = $file;
+			}
+		}
+	} 
 
+	@closedir( $language_plugins_dir );
+
 	if ( empty($plugin_files) )
 		return $dropins;
 
@@ -362,6 +375,21 @@
 			$plugin_data['Name'] = $plugin_file;
 		$dropins[ $plugin_file ] = $plugin_data;
 	}
+	
+	if ( !empty($language_files) ) {
+		foreach ( $language_files as $language_file ) {
+			if ( !is_readable( WP_CONTENT_DIR . '/languages'. "/$language_file" ) ) {
+				continue;
+			}
+			$language_data = array(
+				'Name' => $language_file, 
+				'Title' => $language_file, 
+				'Description' => __('Advanced language file.'), 
+				'Author' => ''
+			);
+			$dropins[ $language_file ] = $language_data;
+		}
+	}
 
 	uksort( $dropins, 'strnatcasecmp' );
 
Index: wp-admin/includes/class-wp-plugins-list-table.php
===================================================================
--- wp-admin/includes/class-wp-plugins-list-table.php	(revision 16578)
+++ wp-admin/includes/class-wp-plugins-list-table.php	(working copy)
@@ -336,8 +336,10 @@
 			$plugin_name = $plugin_file;
 			if ( $plugin_file != $plugin_data['Name'] )
 				$plugin_name .= '<br/>' . $plugin_data['Name'];
-			if ( true === ( $dropins[ $plugin_file ][1] ) ) { // Doesn't require a constant
+			if ( !($dropins[$plugin_file])) { //if not one of the predefined drop-ins, but rather an advanced language file
 				$is_active = true;
+			} elseif ( true === ( $dropins[ $plugin_file ][1] ) ) { // Doesn't require a constant
+				$is_active = true;
 				$description = '<p><strong>' . $dropins[ $plugin_file ][0] . '</strong></p>';
 			} elseif ( constant( $dropins[ $plugin_file ][1] ) ) { // Constant is true
 				$is_active = true;