diff --git a/lib/db/mysql.php b/lib/db/mysql.php
index 841b4db07a7..4ceeabbc385 100644
--- a/lib/db/mysql.php
+++ b/lib/db/mysql.php
@@ -2130,7 +2130,7 @@ function main_upgrade($oldversion=0) {
     }
 
     if ($oldversion < 2006082800) {
-        table_column('user', '', 'ajax', 'integer', '1', 'unsigned', '1', '', 'htmleditor');
+        table_column('user', '', 'ajax', 'integer', '1', 'unsigned', '1', 'not null', 'htmleditor');
     }
 
     if ($oldversion < 2006082900) {
diff --git a/lib/db/postgres7.php b/lib/db/postgres7.php
index b2a4c1c3f71..41ffe246815 100644
--- a/lib/db/postgres7.php
+++ b/lib/db/postgres7.php
@@ -1728,7 +1728,7 @@ function main_upgrade($oldversion=0) {
     }
 
     if ($oldversion < 2006082800) {
-        table_column('user', '', 'ajax', 'integer', '1', 'unsigned', '1', '', 'htmleditor');
+        table_column('user', '', 'ajax', 'integer', '1', 'unsigned', '1', 'not null', 'htmleditor');
     }
 
     if ($oldversion < 2006082900) {