diff --git a/mollom.drupal.inc b/mollom.drupal.inc
index d5ffe7d..a2eaa99 100644
--- a/mollom.drupal.inc
+++ b/mollom.drupal.inc
@@ -314,6 +314,21 @@ class MollomDrupalTest extends MollomDrupal {
     $this->saveConfiguration('publicKey', $this->publicKey);
     $this->saveConfiguration('privateKey', $this->privateKey);
   }
+
+  /**
+   * Overrides Mollom::createCaptcha().
+   *
+   * Temporary fix to show proper image CAPTCHAs when testing mode is enabled.
+   *
+   * @todo Remove after REST Testing API has been fixed.
+   */
+  public function createCaptcha(array $data = array()) {
+    $result = parent::createCaptcha($data);
+    if (isset($data['type']) && $data['type'] === 'image' && isset($result['url']) && strpos($result['url'], 'some-url-to-a-captcha') !== FALSE) {
+      $result['url'] = '//rest.mollom.com/' . self::API_VERSION . '/captcha/image/test.png';
+    }
+    return $result;
+  }
 }
 
 /**