diff --git a/token_custom.module b/token_custom.module
index 06de8f0..927c665 100644
--- a/token_custom.module
+++ b/token_custom.module
@@ -485,11 +485,11 @@ function token_custom_token_render($machine_name, $code, $data, $options) {
    */
   if ($format == 'php_code') {
 
-    /*
-     * Add a random hash to make sure no other encapsulated token_replace call
-     * will get the same (or change) this $data array.
-     */
-    $static_key = 'token_custom_' . drupal_random_bytes(10);
+    // Build a stack of static keys.
+    $static_count = &drupal_static('token_custom_data:count', 0);
+
+    // Generate static key from current stack count.
+    $static_key = 'token_custom_data:' . $static_count;
 
     /*
      * Store value in static cache and leave it there.
@@ -500,6 +500,9 @@ function token_custom_token_render($machine_name, $code, $data, $options) {
                     'options' => $options,
                   ));
 
+    // Push a level onto the static stack.
+    $static_count ++;
+
     // Add static data to the evaluated code.
     $code = '
 <?php
@@ -508,6 +511,11 @@ function token_custom_token_render($machine_name, $code, $data, $options) {
   } ?>' . $code;
 
     $output = check_markup($code, $format);
+
+    // Pop a level off the static stack.
+    $static_count --;
+    drupal_static_reset($static_key);
+
     return $output;
   }
   else {