diff --git a/cas.install b/cas.install
index 8c481be..ce0634b 100644
--- a/cas.install
+++ b/cas.install
@@ -348,3 +348,20 @@ function cas_update_7000(&$sandbox) {
   $moved_deltas = array();
   update_fix_d7_block_deltas($sandbox, $renamed_deltas, $moved_deltas);
 }
+
+/**
+ * Set the CAS' weight to be higher than rules' if it exists.
+ */
+function cas_update_7100(&$sandbox) {
+  if (module_exists('rules')) {
+    $rules_weight = db_select('system', 's')
+      ->fields('s', array('weight'))
+      ->condition('name', 'rules', '=')
+      ->execute()
+      ->fetchField();
+    db_update('system')
+      ->fields(array('weight' => $rules_weight +1))
+      ->condition('name', 'cas', '=')
+      ->execute();
+  }
+}