diff --git a/sites/default/default.settings.php b/sites/default/default.settings.php
index 70c6480..14fe2b0 100644
--- a/sites/default/default.settings.php
+++ b/sites/default/default.settings.php
@@ -153,6 +153,16 @@ $update_free_access = FALSE;
  * settings are used there. Settings defined here should not be
  * duplicated there so as to avoid conflict issues.
  */
+
+/**
+ * Some distributions of Linux (most notably Debian) ship their PHP
+ * installations with garbage collection (gc) disabled. Since Drupal depends on
+ * PHP's garbage collection for clearing sessions, ensure that garbage
+ * collection occurs by using the most common settings.
+ */
+ini_set('session.gc_probability', 1);
+ini_set('session.gc_divisor', 100);
+
 ini_set('arg_separator.output',     '&amp;');
 ini_set('magic_quotes_runtime',     0);
 ini_set('magic_quotes_sybase',      0);
