Bug in script/generate

if i want to generate a controller e.g. "news" with script/generate controller news everything went fine... after this i want to create an controller like "admin:news" it will fail with the following error:

The name 'Admin::NewsHelper' is either already used in your application or reserved by Ruby on Rails. Please choose an alternative and run this generator again.

But this helper isnt present, its a false positiv. i i move the "mv app/helpers/news_helper.rb ." and start again, than it works, after that i copy the helper back "v news_helper.rb app/helpers/"

please fix this false positiv

thanks