diff --git a/panels.install b/panels.install
index ebb93e0..2df4955 100644
--- a/panels.install
+++ b/panels.install
@@ -437,6 +437,21 @@ function panels_update_7301() {
  * Adding universally unique identifiers to panels.
  */
 function panels_update_7302() {
+
+  $schema = panels_schema_8();
+
+  $new_fields = array(
+    'panels_display' => array('storage_type', 'storage_id'),
+  );
+
+  foreach ($new_fields as $table => $fields) {
+    foreach ($fields as $field_name) {
+      if (!db_field_exists($table, $field_name)) {
+        db_add_field($table, $field_name, $schema[$table]['fields'][$field_name]);
+      }
+    }
+  }
+
   if (!module_load_include('inc', 'ctools', 'includes/uuid')) {
     throw new DrupalUpdateException(t('Ctools UUID support not detected. You must update to a more recent version of the ctools module.'));
   }
@@ -551,7 +566,9 @@ function panels_update_7305() {
 
   foreach ($new_fields as $table => $fields) {
     foreach ($fields as $field_name) {
-      db_add_field($table, $field_name, $schema[$table]['fields'][$field_name]);
+      if (!db_field_exists($table, $field_name)) {
+        db_add_field($table, $field_name, $schema[$table]['fields'][$field_name]);
+      }
     }
   }
 }