--- plugins/sent_subfolders/setup.php.orig<---->2012-08-24 16:02:20.000000000 +0300
+++ plugins/sent_subfolders/setup.php<->2012-08-24 16:53:02.000000000 +0300
@@ -172,8 +172,11 @@
     } else {
         setPref($data_dir, $username, 'use_sent_subfolders', SMPREF_ON);
         setPref($data_dir, $username, 'move_to_sent', SMPREF_ON);
+        $check_sent_subfolders_base = getPref($data_dir,$username,'sent_subfolders_base','');
+        if ($check_sent_subfolders_base === '') {
+            setPref($data_dir,$username,'sent_subfolders_base',$sent_subfolders_base);
+        }
     }
-
     /* Now just save the option as normal. */
     save_option($option);
 }