I have the following setup using mecached:

class Collection < ActiveRecord::Base
cache_records :key => 'collection'

my methods

end

whenever i try to save or edit a record that i have tried to edit before, I get a stacktrace like this, only if i have the record-cache enabled...

ActionView::Template::Error (no member 'completed_fame' in struct):
1: = form.send field.view_helper, field.method_name, field.html_attributes.reverse_merge((hdv = field.html_default_value).nil? ? {} : { :value => hdv, :checked => hdv })
activerecord (3.2.0) lib/active_record/store.rb:44:in []' activerecord (3.2.0) lib/active_record/store.rb:44:inblock (2 levels) in store_accessor'
/myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/lib/rails_admin/abstract_object.rb:21:in method_missing' actionpack (3.2.0) lib/action_view/helpers/form_helper.rb:1154:invalue_before_type_cast'
actionpack (3.2.0) lib/action_view/helpers/form_helper.rb:1142:in value_before_type_cast' actionpack (3.2.0) lib/action_view/helpers/form_helper.rb:1036:inblock in to_input_field_tag'
actionpack (3.2.0) lib/action_view/helpers/form_helper.rb:1036:in fetch' actionpack (3.2.0) lib/action_view/helpers/form_helper.rb:1036:into_input_field_tag'
actionpack (3.2.0) lib/action_view/helpers/form_helper.rb:1049:in to_number_field_tag' actionpack (3.2.0) lib/action_view/helpers/form_helper.rb:938:innumber_field'
actionpack (3.2.0) lib/action_view/helpers/form_helper.rb:1277:in number_field' /myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/views/rails_admin/main/_form_field.html.haml:1:in__mnt_data_myapp_shared_bundle_ruby_______bundler_gems_rails_admin____________f_app_views_rails_admin_main__form_field_html_haml__1921039710147814407_47694540'
actionpack (3.2.0) lib/action_view/template.rb:143:in block in render' activesupport (3.2.0) lib/active_support/notifications.rb:125:ininstrument'
actionpack (3.2.0) lib/action_view/template.rb:141:in render' actionpack (3.2.0) lib/action_view/renderer/partial_renderer.rb:257:inrender_partial'
actionpack (3.2.0) lib/action_view/renderer/partial_renderer.rb:230:in block in render' actionpack (3.2.0) lib/action_view/renderer/abstract_renderer.rb:38:inblock in instrument'
activesupport (3.2.0) lib/active_support/notifications.rb:123:in block in instrument' activesupport (3.2.0) lib/active_support/notifications/instrumenter.rb:20:ininstrument'
activesupport (3.2.0) lib/active_support/notifications.rb:123:in instrument' actionpack (3.2.0) lib/action_view/renderer/abstract_renderer.rb:38:ininstrument'
actionpack (3.2.0) lib/action_view/renderer/partial_renderer.rb:229:in render' actionpack (3.2.0) lib/action_view/renderer/renderer.rb:41:inrender_partial'
actionpack (3.2.0) lib/action_view/renderer/renderer.rb:15:in render' actionpack (3.2.0) lib/action_view/helpers/rendering_helper.rb:24:inrender'
haml (3.1.4) lib/haml/helpers/action_view_mods.rb:11:in block in render_with_haml' haml (3.1.4) lib/haml/helpers.rb:90:innon_haml'
haml (3.1.4) lib/haml/helpers/action_view_mods.rb:11:in render_with_haml' /myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/lib/rails_admin/config/fields/base.rb:211:inrender'
/myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/lib/rails_admin/config/proxy.rb:29:in method_missing' /myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/helpers/rails_admin/form_builder.rb:68:infield_for'
/myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/helpers/rails_admin/form_builder.rb:50:in block in input_for' actionpack (3.2.0) lib/action_view/helpers/capture_helper.rb:40:inblock in capture'
actionpack (3.2.0) lib/action_view/helpers/capture_helper.rb:187:in with_output_buffer' haml (3.1.4) lib/haml/helpers/xss_mods.rb:109:inwith_output_buffer_with_haml_xss'
actionpack (3.2.0) lib/action_view/helpers/capture_helper.rb:40:in capture' haml (3.1.4) lib/haml/helpers/action_view_mods.rb:105:incapture_with_haml'
actionpack (3.2.0) lib/action_view/helpers/tag_helper.rb:91:in content_tag' haml (3.1.4) lib/haml/helpers/action_view_mods.rb:123:incontent_tag_with_haml'
/myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/helpers/rails_admin/form_builder.rb:49:in input_for' /myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/helpers/rails_admin/form_builder.rb:42:inblock in field_wrapper_for'
actionpack (3.2.0) lib/action_view/helpers/capture_helper.rb:40:in block in capture' actionpack (3.2.0) lib/action_view/helpers/capture_helper.rb:187:inwith_output_buffer'
haml (3.1.4) lib/haml/helpers/xss_mods.rb:109:in with_output_buffer_with_haml_xss' actionpack (3.2.0) lib/action_view/helpers/capture_helper.rb:40:incapture'
haml (3.1.4) lib/haml/helpers/action_view_mods.rb:105:in capture_with_haml' actionpack (3.2.0) lib/action_view/helpers/tag_helper.rb:91:incontent_tag'
haml (3.1.4) lib/haml/helpers/action_view_mods.rb:123:in content_tag_with_haml' /myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/helpers/rails_admin/form_builder.rb:40:infield_wrapper_for'
/myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/helpers/rails_admin/form_builder.rb:28:in block (2 levels) in fieldset_for' /myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/helpers/rails_admin/form_builder.rb:28:inmap'
/myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/helpers/rails_admin/form_builder.rb:28:in block in fieldset_for' actionpack (3.2.0) lib/action_view/helpers/capture_helper.rb:40:inblock in capture'
actionpack (3.2.0) lib/action_view/helpers/capture_helper.rb:187:in with_output_buffer' haml (3.1.4) lib/haml/helpers/xss_mods.rb:109:inwith_output_buffer_with_haml_xss'
actionpack (3.2.0) lib/action_view/helpers/capture_helper.rb:40:in capture' haml (3.1.4) lib/haml/helpers/action_view_mods.rb:105:incapture_with_haml'
actionpack (3.2.0) lib/action_view/helpers/tag_helper.rb:91:in content_tag' haml (3.1.4) lib/haml/helpers/action_view_mods.rb:123:incontent_tag_with_haml'
/myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/helpers/rails_admin/form_builder.rb:24:in fieldset_for' /myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/helpers/rails_admin/form_builder.rb:17:inblock in generate'
/myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/helpers/rails_admin/form_builder.rb:16:in map' /myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/helpers/rails_admin/form_builder.rb:16:ingenerate'
/myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/views/rails_admin/main/edit.html.haml:2:in block in __mnt_data_myapp_shared_bundle_ruby_______bundler_gems_rails_admin____________f_app_views_rails_admin_main_edit_html_haml__2936297698482363203_49865300' haml (3.1.4) lib/haml/helpers/action_view_mods.rb:181:incall'
haml (3.1.4) lib/haml/helpers/action_view_mods.rb:181:in block (2 levels) in form_for_with_haml' haml (3.1.4) lib/haml/helpers.rb:255:inwith_tabs'
haml (3.1.4) lib/haml/helpers/action_view_mods.rb:181:in block in form_for_with_haml' actionpack (3.2.0) lib/action_view/helpers/capture_helper.rb:40:inblock in capture'
actionpack (3.2.0) lib/action_view/helpers/capture_helper.rb:187:in with_output_buffer' haml (3.1.4) lib/haml/helpers/xss_mods.rb:109:inwith_output_buffer_with_haml_xss'
actionpack (3.2.0) lib/action_view/helpers/capture_helper.rb:40:in capture' haml (3.1.4) lib/haml/helpers/action_view_mods.rb:105:incapture_with_haml'
actionpack (3.2.0) lib/action_view/helpers/form_helper.rb:606:in fields_for' actionpack (3.2.0) lib/action_view/helpers/form_helper.rb:377:inform_for'
haml (3.1.4) lib/haml/helpers/action_view_mods.rb:183:in form_for_with_haml' haml (3.1.4) lib/haml/helpers/xss_mods.rb:132:inform_for_with_haml_xss'
/myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/helpers/rails_admin/main_helper.rb:7:in rails_admin_form_for' /myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/app/views/rails_admin/main/edit.html.haml:1:in__mnt_data_myapp_shared_bundle_ruby_______bundler_gems_rails_admin____________f_app_views_rails_admin_main_edit_html_haml__2936297698482363203_49865300'
actionpack (3.2.0) lib/action_view/template.rb:143:in block in render' activesupport (3.2.0) lib/active_support/notifications.rb:125:ininstrument'
actionpack (3.2.0) lib/action_view/template.rb:141:in render' actionpack (3.2.0) lib/action_view/renderer/template_renderer.rb:41:inblock (2 levels) in render_template'
actionpack (3.2.0) lib/action_view/renderer/abstract_renderer.rb:38:in block in instrument' activesupport (3.2.0) lib/active_support/notifications.rb:123:inblock in instrument'
activesupport (3.2.0) lib/active_support/notifications/instrumenter.rb:20:in instrument' activesupport (3.2.0) lib/active_support/notifications.rb:123:ininstrument'
actionpack (3.2.0) lib/action_view/renderer/abstract_renderer.rb:38:in instrument' actionpack (3.2.0) lib/action_view/renderer/template_renderer.rb:40:inblock in render_template'
actionpack (3.2.0) lib/action_view/renderer/template_renderer.rb:48:in render_with_layout' actionpack (3.2.0) lib/action_view/renderer/template_renderer.rb:39:inrender_template'
actionpack (3.2.0) lib/action_view/renderer/template_renderer.rb:12:in render' actionpack (3.2.0) lib/action_view/renderer/renderer.rb:36:inrender_template'
actionpack (3.2.0) lib/action_view/renderer/renderer.rb:17:in render' actionpack (3.2.0) lib/abstract_controller/rendering.rb:109:in_render_template'
actionpack (3.2.0) lib/action_controller/metal/streaming.rb:225:in _render_template' actionpack (3.2.0) lib/abstract_controller/rendering.rb:103:inrender_to_body'
actionpack (3.2.0) lib/action_controller/metal/renderers.rb:28:in render_to_body' actionpack (3.2.0) lib/action_controller/metal/compatibility.rb:50:inrender_to_body'
actionpack (3.2.0) lib/abstract_controller/rendering.rb:88:in render' actionpack (3.2.0) lib/action_controller/metal/rendering.rb:16:inrender'
actionpack (3.2.0) lib/action_controller/metal/instrumentation.rb:40:in block (2 levels) in render' activesupport (3.2.0) lib/active_support/core_ext/benchmark.rb:5:inblock in ms'
/usr/lib/ruby/1.9.1/benchmark.rb:309:in realtime' activesupport (3.2.0) lib/active_support/core_ext/benchmark.rb:5:inms'
actionpack (3.2.0) lib/action_controller/metal/instrumentation.rb:40:in block in render' actionpack (3.2.0) lib/action_controller/metal/instrumentation.rb:83:incleanup_view_runtime'
activerecord (3.2.0) lib/active_record/railties/controller_runtime.rb:24:in cleanup_view_runtime' actionpack (3.2.0) lib/action_controller/metal/instrumentation.rb:39:inrender'
remotipart (1.0.2) lib/remotipart/render_overrides.rb:8:in render' /myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/lib/rails_admin/config/actions/edit.rb:21:inblock (4 levels) in class:Edit'
actionpack (3.2.0) lib/action_controller/metal/mime_responds.rb:195:in call' actionpack (3.2.0) lib/action_controller/metal/mime_responds.rb:195:inrespond_to'
/myapp_path//shared/bundle/ruby/1.9.1/bundler/gems/rails_admin-05315224490f/lib/rails_admin/config/actions/edit.rb:20:in block (2 levels) in <class:Edit>' (eval):9:ininstance_eval'
(eval):9:in edit' actionpack (3.2.0) lib/action_controller/metal/implicit_render.rb:4:insend_action'
actionpack (3.2.0) lib/abstract_controller/base.rb:167:in process_action' actionpack (3.2.0) lib/action_controller/metal/rendering.rb:10:inprocess_action'
actionpack (3.2.0) lib/abstract_controller/callbacks.rb:18:in block in process_action' activesupport (3.2.0) lib/active_support/callbacks.rb:491:in_run__712079326750545375__process_action__810452953766824551__callbacks'
activesupport (3.2.0) lib/active_support/callbacks.rb:405:in __run_callback' activesupport (3.2.0) lib/active_support/callbacks.rb:385:in_run_process_action_callbacks'
activesupport (3.2.0) lib/active_support/callbacks.rb:81:in run_callbacks' actionpack (3.2.0) lib/abstract_controller/callbacks.rb:17:inprocess_action'
actionpack (3.2.0) lib/action_controller/metal/rescue.rb:29:in process_action' actionpack (3.2.0) lib/action_controller/metal/instrumentation.rb:30:inblock in process_action'
activesupport (3.2.0) lib/active_support/notifications.rb:123:in block in instrument' activesupport (3.2.0) lib/active_support/notifications/instrumenter.rb:20:ininstrument'
activesupport (3.2.0) lib/active_support/notifications.rb:123:in instrument' actionpack (3.2.0) lib/action_controller/metal/instrumentation.rb:29:inprocess_action'
actionpack (3.2.0) lib/action_controller/metal/params_wrapper.rb:205:in process_action' activerecord (3.2.0) lib/active_record/railties/controller_runtime.rb:18:inprocess_action'
newrelic_rpm (3.3.1) lib/new_relic/agent/instrumentation/rails3/action_controller.rb:34:in block in process_action' newrelic_rpm (3.3.1) lib/new_relic/agent/instrumentation/controller_instrumentation.rb:255:inblock in perform_action_with_newrelic_trace'
newrelic_rpm (3.3.1) lib/new_relic/agent/method_tracer.rb:242:in trace_execution_scoped' newrelic_rpm (3.3.1) lib/new_relic/agent/instrumentation/controller_instrumentation.rb:250:inperform_action_with_newrelic_trace'
newrelic_rpm (3.3.1) lib/new_relic/agent/instrumentation/rails3/action_controller.rb:33:in process_action' actionpack (3.2.0) lib/abstract_controller/base.rb:121:inprocess'
actionpack (3.2.0) lib/abstract_controller/rendering.rb:45:in process' actionpack (3.2.0) lib/action_controller/metal.rb:203:indispatch'
actionpack (3.2.0) lib/action_controller/metal/rack_delegation.rb:14:in dispatch' actionpack (3.2.0) lib/action_controller/metal.rb:246:inblock in action'
actionpack (3.2.0) lib/action_dispatch/routing/route_set.rb:66:in call' actionpack (3.2.0) lib/action_dispatch/routing/route_set.rb:66:indispatch'
actionpack (3.2.0) lib/action_dispatch/routing/route_set.rb:30:in call' journey (1.0.1) lib/journey/router.rb:68:inblock in call'
journey (1.0.1) lib/journey/router.rb:56:in each' journey (1.0.1) lib/journey/router.rb:56:incall'
actionpack (3.2.0) lib/action_dispatch/routing/route_set.rb:570:in call' railties (3.2.0) lib/rails/engine.rb:479:incall'
railties (3.2.0) lib/rails/railtie/configurable.rb:30:in method_missing' journey (1.0.1) lib/journey/router.rb:68:inblock in call'
journey (1.0.1) lib/journey/router.rb:56:in each' journey (1.0.1) lib/journey/router.rb:56:incall'
actionpack (3.2.0) lib/action_dispatch/routing/route_set.rb:570:in call' rack-pjax (0.5.7) lib/rack/pjax.rb:12:incall'
omniauth (1.0.2) lib/omniauth/strategy.rb:168:in call!' omniauth (1.0.2) lib/omniauth/strategy.rb:148:incall'
newrelic_rpm (3.3.1) lib/new_relic/rack/browser_monitoring.rb:23:in call' warden (1.1.0) lib/warden/manager.rb:35:inblock in call'
warden (1.1.0) lib/warden/manager.rb:34:in catch' warden (1.1.0) lib/warden/manager.rb:34:incall'
actionpack (3.2.0) lib/action_dispatch/middleware/best_standards_support.rb:17:in call' rack (1.4.1) lib/rack/etag.rb:23:incall'
rack (1.4.1) lib/rack/conditionalget.rb:25:in call' actionpack (3.2.0) lib/action_dispatch/middleware/head.rb:14:incall'
remotipart (1.0.2) lib/remotipart/middleware.rb:30:in call' actionpack (3.2.0) lib/action_dispatch/middleware/params_parser.rb:21:incall'
actionpack (3.2.0) lib/action_dispatch/middleware/flash.rb:242:in call' rack (1.4.1) lib/rack/session/abstract/id.rb:205:incontext'
rack (1.4.1) lib/rack/session/abstract/id.rb:200:in call' actionpack (3.2.0) lib/action_dispatch/middleware/cookies.rb:338:incall'
activerecord (3.2.0) lib/active_record/query_cache.rb:64:in call' activerecord (3.2.0) lib/active_record/connection_adapters/abstract/connection_pool.rb:443:incall'
actionpack (3.2.0) lib/action_dispatch/middleware/callbacks.rb:28:in block in call' activesupport (3.2.0) lib/active_support/callbacks.rb:405:in_run__2606656878487081079__call__415961845225187871__callbacks'
activesupport (3.2.0) lib/active_support/callbacks.rb:405:in __run_callback' activesupport (3.2.0) lib/active_support/callbacks.rb:385:in_run_call_callbacks'
activesupport (3.2.0) lib/active_support/callbacks.rb:81:in run_callbacks' actionpack (3.2.0) lib/action_dispatch/middleware/callbacks.rb:27:incall'
actionpack (3.2.0) lib/action_dispatch/middleware/remote_ip.rb:31:in call' actionpack (3.2.0) lib/action_dispatch/middleware/debug_exceptions.rb:16:incall'
actionpack (3.2.0) lib/action_dispatch/middleware/show_exceptions.rb:56:in call' railties (3.2.0) lib/rails/rack/logger.rb:26:incall_app'
railties (3.2.0) lib/rails/rack/logger.rb:16:in call' actionpack (3.2.0) lib/action_dispatch/middleware/request_id.rb:22:incall'
rack (1.4.1) lib/rack/methodoverride.rb:21:in call' rack (1.4.1) lib/rack/runtime.rb:17:incall'
activesupport (3.2.0) lib/active_support/cache/strategy/local_cache.rb:72:in call' rack (1.4.1) lib/rack/lock.rb:15:incall'
railties (3.2.0) lib/rails/engine.rb:479:in call' railties (3.2.0) lib/rails/application.rb:220:incall'
railties (3.2.0) lib/rails/railtie/configurable.rb:30:in method_missing' unicorn (4.2.0) lib/unicorn/http_server.rb:530:inprocess_client'
unicorn (4.2.0) lib/unicorn/http_server.rb:604:in worker_loop' newrelic_rpm (3.3.1) lib/new_relic/agent/instrumentation/unicorn_instrumentation.rb:17:incall'
newrelic_rpm (3.3.1) lib/new_relic/agent/instrumentation/unicorn_instrumentation.rb:17:in block (4 levels) in <top (required)>' unicorn (4.2.0) lib/unicorn/http_server.rb:487:inspawn_missing_workers'
unicorn (4.2.0) lib/unicorn/http_server.rb:137:in start' unicorn (4.2.0) bin/unicorn:121:in<top (required)>'
/myapp_path//shared/bundle/ruby/1.9.1/bin/unicorn:19:in load' /myapp_path//shared/bundle/ruby/1.9.1/bin/unicorn:19:in