ruby on rails - heroku postgressql db migration error -

ruby on rails - heroku postgressql db migration error -

i'm getting error when seek migrate postgres database in heroku. first got:

$ heroku run rake db:migrate --trace rake aborted! undefined method `find_by_name' gem::specification:class /app/lib/tasks/auto_annotate_models.rake:22:in `<top (required)>' /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.11/lib/active_support/depen dencies.rb:245:in `load' /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.11/lib/active_support/depen dencies.rb:245:in `block in load' /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.11/lib/active_support/depen dencies.rb:236:in `load_dependency' /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.11/lib/active_support/depen dencies.rb:245:in `load' /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.11/lib/rails/engine.rb:425:in `b lock in load_tasks' /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.11/lib/rails/engine.rb:425:in `e ach' /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.11/lib/rails/engine.rb:425:in `l oad_tasks' /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.11/lib/rails/application.rb:145: in `load_tasks' /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.11/lib/rails/railtie/configurabl e.rb:30:in `method_missing' /app/rakefile:7:in `<top (required)>' /app/vendor/bundle/ruby/1.9.1/gems/rake-10.0.3/lib/rake/rake_module.rb:25:in `lo ad' /app/vendor/bundle/ruby/1.9.1/gems/rake-10.0.3/lib/rake/rake_module.rb:25:in `lo ad_rakefile' /app/vendor/bundle/ruby/1.9.1/gems/rake-10.0.3/lib/rake/application.rb:583:in `r aw_load_rakefile' /app/vendor/bundle/ruby/1.9.1/gems/rake-10.0.3/lib/rake/application.rb:89:in `bl ock in load_rakefile' /app/vendor/bundle/ruby/1.9.1/gems/rake-10.0.3/lib/rake/application.rb:160:in `s tandard_exception_handling' /app/vendor/bundle/ruby/1.9.1/gems/rake-10.0.3/lib/rake/application.rb:88:in `lo ad_rakefile' /app/vendor/bundle/ruby/1.9.1/gems/rake-10.0.3/lib/rake/application.rb:72:in `bl ock in run' /app/vendor/bundle/ruby/1.9.1/gems/rake-10.0.3/lib/rake/application.rb:160:in `s tandard_exception_handling' /app/vendor/bundle/ruby/1.9.1/gems/rake-10.0.3/lib/rake/application.rb:70:in `ru n' /app/vendor/bundle/ruby/1.9.1/gems/rake-10.0.3/bin/rake:33:in `<top (required)>' /app/vendor/bundle/ruby/1.9.1/bin/rake:19:in `load' /app/vendor/bundle/ruby/1.9.1/bin/rake:19:in `<main>'

does know what's going on?

did heroku run rake db:create before migrate?

ruby-on-rails postgresql heroku