diff --git a/lib/tasks/migrate_from_mantis.rake b/lib/tasks/migrate_from_mantis.rake
index 5eb1160dd..4f6f18527 100644
--- a/lib/tasks/migrate_from_mantis.rake
+++ b/lib/tasks/migrate_from_mantis.rake
@@ -471,7 +471,7 @@ task :migrate_from_mantis => :environment do
   puts
   
   # Make sure bugs can refer bugs in other projects
-  Setting.cross_project_issue_relations = 1
+  Setting.cross_project_issue_relations = 1 if Setting.respond_to? 'cross_project_issue_relations'
   
   MantisMigrate.establish_connection db_params
   MantisMigrate.migrate