diff --git a/includes/bootstrap.inc b/includes/bootstrap.inc
index decb911..218b1d8 100644
--- a/includes/bootstrap.inc
+++ b/includes/bootstrap.inc
@@ -918,7 +918,28 @@ function variable_initialize($conf = array()) {
     }
     else {
       // Proceed with variable rebuild.
-      $variables = array_map('unserialize', db_query('SELECT name, value FROM {variable}')->fetchAllKeyed());
+      $variables = array();
+      // We can run into unparsable values
+      $err_variables = array();
+      $rows = db_query('SELECT name, value FROM {variable}')->fetchAllKeyed();
+      foreach ($rows as $name => $db_value) {
+        // Suppress the notice.
+        $value = @unserialize($db_value);
+        // If the unserialize call returned FALSE and the stored value is NOT a
+        // boolean false, list it in the report.
+        if ($value === FALSE && $db_value !== serialize(FALSE) && !isset($conf[$name])) {
+          $err_variables[] = $name;
+        }
+        $variables[$name] = $value;
+      }
+      // We throw an exception before storing the variables otherwise
+      // this exception is only thrown once which is bad
+      if (count($err_variables)) {
+        $t = get_t();
+        $err_vars = join ("', '", $err_variables);
+        $err_str = "The variable(s) '@err_vars' are unreadable and need to be fixed. Please read UPGRADE.txt on how to resolve this problem.";
+        throw new Exception($t($err_str, array('@err_vars' => $err_vars)));
+      }
       cache_set('variables', $variables, 'cache_bootstrap');
       lock_release($name);
     }