Improve uppercase/lowercase/ucfirst attrib handling in rcube::gettext()

- Make ucfirst mode compatible with UTF-8
- Fix bug which made uppercase=FIRST non-working
- Replace \n with real line-break before converting char case

program/lib/Roundcube/rcube.php

@@ -599,7 +599,7 @@ class rcube
      *
      * @return string Localized text
      */
-    public function gettext($attrib, $domain=null)
+    public function gettext($attrib, $domain = null)
     {
         // load localization files if not done yet
         if (empty($this->texts)) {
@@ -633,18 +633,25 @@ class rcube
             }
         }
 
-        // format output
-        if (($attrib['uppercase'] && strtolower($attrib['uppercase'] == 'first')) || $attrib['ucfirst']) {
-            return ucfirst($text);
+        // replace \n with real line break
+        $text = strtr($text, array('\n' => "\n"));
+
+        // case folding
+        if (($attrib['uppercase'] && strtolower($attrib['uppercase']) == 'first') || $attrib['ucfirst']) {
+            $case_mode = MB_CASE_TITLE;
         }
         else if ($attrib['uppercase']) {
-            return mb_strtoupper($text);
+            $case_mode = MB_CASE_UPPER;
         }
         else if ($attrib['lowercase']) {
-            return mb_strtolower($text);
+            $case_mode = MB_CASE_LOWER;
+        }
+
+        if (isset($case_mode)) {
+            $text = mb_convert_case($text, $case_mode);
         }
 
-        return strtr($text, array('\n' => "\n"));
+        return $text;
     }
 
     /**