Update Character.php (#833)

classes/phing/system/lang/Character.php

@@ -24,32 +24,12 @@
  */
 class Character
 {
-
-    // this class might be extended with plenty of ordinal char constants
-    // and the like to support the multibyte aware datatype (char) in php
-    // in form of an object.
-    // anyway just a thought
-
     /**
      * @param $char
      * @return bool
      */
     public static function isLetter($char)
     {
-        if (strlen($char) !== 1) {
-            $char = 0;
-        }
-
-        $char = (int) ord($char);
-
-        if ($char >= ord('A') && $char <= ord('Z')) {
-            return true;
-        }
-
-        if ($char >= ord('a') && $char <= ord('z')) {
-            return true;
-        }
-
-        return false;
+        return strlen($char) === 1 && ctype_alpha($char);
     }
 }