TWeak to version81 upgrade function

diff --git a/src/library/VersionFunctions.php b/src/library/VersionFunctions.php
index 803b7605c..3e3134117 100644
--- a/src/library/VersionFunctions.php
+++ b/src/library/VersionFunctions.php
@@ -2185,6 +2185,7 @@ function upgradeDatabaseVersion80(&$db)
 function upgradeDatabaseVersion81(&$db)
 {
     $profile_model = new M\ProfileModel(C\DB_NAME, false);
+    $profile_model->db = $db;
     $profile = $profile_model->getProfile(C\WORK_DIRECTORY);
     $new_profile = $profile;
     $new_profile['WIKI_BONUS']= 0.5;