Redmine

Hi,

I am attempting to install the backlogs plugin, however when I try and perform a rake..
rake db:migrate:upgrade_plugin_migrations RAILS_ENV=production

I get the error:

rake aborted!
undefined method 'safe_attributes' for #<Class:0x7ff476deea00>

Can anyone please tell me how I can troubleshoot this and any more information I should provide to help me fix this?

Thanks for any help!