Index: captcha.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/captcha/captcha.module,v
retrieving revision 1.100
diff -u -b -u -p -r1.100 captcha.module
--- captcha.module	20 Sep 2009 10:57:07 -0000	1.100
+++ captcha.module	3 Nov 2009 22:47:37 -0000
@@ -401,7 +401,6 @@ function captcha_validate_case_insensiti
  * captcha_form_alter(), and subsequently don't include additional include
  * files).
  */
-
 function captcha_validate($element, &$form_state) {
   $captcha_info = $element['#captcha_info'];
   $form_id = $captcha_info['form_id'];
Index: image_captcha/image_captcha.user.inc
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/captcha/image_captcha/image_captcha.user.inc,v
retrieving revision 1.21
diff -u -b -u -p -r1.21 image_captcha.user.inc
--- image_captcha/image_captcha.user.inc	22 Sep 2009 22:51:00 -0000	1.21
+++ image_captcha/image_captcha.user.inc	3 Nov 2009 22:47:37 -0000
@@ -98,7 +98,9 @@ function _image_captcha_generate_image($
   imagefilledrectangle($image, 0, 0, $width, $height, $background_color);
 
   // draw text
-  $result = _image_captcha_image_generator_print_string($image, $width, $height, $font, $font_size, $code);
+  global $language;
+  $rtl = (defined('LANGUAGE_RTL') && $language->direction == LANGUAGE_RTL); // @todo: the check if LANGUAGE_RTL is defined can be dropped for Drupal 7.
+  $result = _image_captcha_image_generator_print_string($image, $width, $height, $font, $font_size, $code, $rtl);
   if (!$result) {
     return FALSE;
   }
@@ -231,7 +233,7 @@ function _image_captcha_image_generator_
 /**
  * Helper function for drawing text on the image.
  */
-function _image_captcha_image_generator_print_string(&$image, $width, $height, $font, $font_size, $text) {
+function _image_captcha_image_generator_print_string(&$image, $width, $height, $font, $font_size, $text, $rtl=FALSE) {
   // get characters
   $characters = _image_captcha_utf8_split($text);
   $character_quantity = count($characters);
@@ -268,6 +270,9 @@ function _image_captcha_image_generator_
   foreach ($characters as $c => $character) {
     // initial position of character: in the center of its cage
     $center_x = ($c + 0.5) * $ccage_width;
+    if ($rtl) {
+      $center_x = $width - $center_x;
+    }
     $center_y = 0.5 * $height;
 
     // get character dimensions for ttf fonts