diff --git a/db/migrate/010_add_admin_and_roles.rb b/db/migrate/010_add_admin_and_roles.rb
--- a/db/migrate/010_add_admin_and_roles.rb
+++ b/db/migrate/010_add_admin_and_roles.rb
@@ -9,6 +9,9 @@
 
     class << root
       public :encrypt_new_password
+      def valid?
+        true
+      end
     end
 
     root.encrypt_new_password
diff --git a/db/migrate/025_add_site_to_user_and_add_default_site.rb b/db/migrate/025_add_site_to_user_and_add_default_site.rb
--- a/db/migrate/025_add_site_to_user_and_add_default_site.rb
+++ b/db/migrate/025_add_site_to_user_and_add_default_site.rb
@@ -8,6 +8,13 @@
     User.reset_column_information
 
     User.find(:all).each do |user|
+
+      class << user
+        def valid?
+          true
+        end
+      end
+
       user.site_id = default_site.id
       user.save
     end
diff --git a/db/migrate/031_add_supports_for_output_only_problems.rb b/db/migrate/031_add_supports_for_output_only_problems.rb
--- a/db/migrate/031_add_supports_for_output_only_problems.rb
+++ b/db/migrate/031_add_supports_for_output_only_problems.rb
@@ -6,6 +6,6 @@
 
   def self.down
     remove_column :submissions, :source_filename
-    add_column :problems, :output_only, :boolean
+    remove_column :problems, :output_only
   end
 end
diff --git a/db/migrate/20081204122651_add_activated_to_users.rb b/db/migrate/20081204122651_add_activated_to_users.rb
--- a/db/migrate/20081204122651_add_activated_to_users.rb
+++ b/db/migrate/20081204122651_add_activated_to_users.rb
@@ -2,6 +2,8 @@
   def self.up
     add_column :users, :activated, :boolean, :default => 0
 
+    User.reset_column_information
+
     User.find(:all).each do |user|
 
       # disable validation