Error by adding issues with checklist entries

[bes1002t]

Environment:
Redmine version 3.0.2.stable
Ruby version 2.2.1-p85 (2015-02-26) [armv6l-linux-eabihf]
Rails version 4.2.1
Environment production
Database adapter Mysql2
SCM:
Git 1.7.10.4
Filesystem
Redmine plugins:
redmine_issue_checklist 2.0.8

If I add an issue without checklist entries all is working great.
But if I add an issue with checklist entries I'll get the following error:

NoMethodError (undefined method strip' for nil:NilClass): plugins/redmine_issue_checklist/app/models/issue_checklist.rb:21:ininfo'
activerecord (4.2.1) lib/active_record/relation/delegation.rb:46:in collect' activerecord (4.2.1) lib/active_record/relation/delegation.rb:46:incollect'
plugins/redmine_issue_checklist/lib/redmine_issue_checklist/patches/issue_patch.rb:39:in update_checklist_items' plugins/redmine_issue_checklist/lib/redmine_issue_checklist/patches/issues_controller_patch.rb:13:inbuild_new_issue_from_params_with_checklist'
activesupport (4.2.1) lib/active_support/callbacks.rb:432:in block in make_lambda' activesupport (4.2.1) lib/active_support/callbacks.rb:145:incall'
activesupport (4.2.1) lib/active_support/callbacks.rb:145:in block in halting_and_conditional' activesupport (4.2.1) lib/active_support/callbacks.rb:504:incall'
activesupport (4.2.1) lib/active_support/callbacks.rb:504:in block in call' activesupport (4.2.1) lib/active_support/callbacks.rb:504:ineach'
activesupport (4.2.1) lib/active_support/callbacks.rb:504:in call' activesupport (4.2.1) lib/active_support/callbacks.rb:92:in_run_callbacks'
activesupport (4.2.1) lib/active_support/callbacks.rb:776:in _run_process_action_callbacks' activesupport (4.2.1) lib/active_support/callbacks.rb:81:inrun_callbacks'
actionpack (4.2.1) lib/abstract_controller/callbacks.rb:19:in process_action' actionpack (4.2.1) lib/action_controller/metal/rescue.rb:29:inprocess_action'
actionpack (4.2.1) lib/action_controller/metal/instrumentation.rb:32:in block in process_action' activesupport (4.2.1) lib/active_support/notifications.rb:164:inblock in instrument'
activesupport (4.2.1) lib/active_support/notifications/instrumenter.rb:20:in instrument' activesupport (4.2.1) lib/active_support/notifications.rb:164:ininstrument'
actionpack (4.2.1) lib/action_controller/metal/instrumentation.rb:30:in process_action' actionpack (4.2.1) lib/action_controller/metal/params_wrapper.rb:250:inprocess_action'
activerecord (4.2.1) lib/active_record/railties/controller_runtime.rb:18:in process_action' actionpack (4.2.1) lib/abstract_controller/base.rb:137:inprocess'
actionview (4.2.1) lib/action_view/rendering.rb:30:in process' actionpack (4.2.1) lib/action_controller/metal.rb:196:indispatch'
actionpack (4.2.1) lib/action_controller/metal/rack_delegation.rb:13:in dispatch' actionpack (4.2.1) lib/action_controller/metal.rb:237:inblock in action'
actionpack (4.2.1) lib/action_dispatch/routing/route_set.rb:74:in call' actionpack (4.2.1) lib/action_dispatch/routing/route_set.rb:74:indispatch'
actionpack (4.2.1) lib/action_dispatch/routing/route_set.rb:43:in serve' actionpack (4.2.1) lib/action_dispatch/journey/router.rb:43:inblock in serve'
actionpack (4.2.1) lib/action_dispatch/journey/router.rb:30:in each' actionpack (4.2.1) lib/action_dispatch/journey/router.rb:30:inserve'
actionpack (4.2.1) lib/action_dispatch/routing/route_set.rb:819:in call' rack-openid (1.4.2) lib/rack/openid.rb:98:incall'
request_store (1.0.5) lib/request_store/middleware.rb:9:in call' rack (1.6.1) lib/rack/etag.rb:24:incall'
rack (1.6.1) lib/rack/conditionalget.rb:38:in call' rack (1.6.1) lib/rack/head.rb:13:incall'
actionpack-xml_parser (1.0.2) lib/action_dispatch/xml_params_parser.rb:16:in call' actionpack (4.2.1) lib/action_dispatch/middleware/params_parser.rb:27:incall'
actionpack (4.2.1) lib/action_dispatch/middleware/flash.rb:260:in call' rack (1.6.1) lib/rack/session/abstract/id.rb:225:incontext'
rack (1.6.1) lib/rack/session/abstract/id.rb:220:in call' actionpack (4.2.1) lib/action_dispatch/middleware/cookies.rb:560:incall'
activerecord (4.2.1) lib/active_record/query_cache.rb:36:in call' activerecord (4.2.1) lib/active_record/connection_adapters/abstract/connection_pool.rb:649:incall'
actionpack (4.2.1) lib/action_dispatch/middleware/callbacks.rb:29:in block in call' activesupport (4.2.1) lib/active_support/callbacks.rb:88:incall'
activesupport (4.2.1) lib/active_support/callbacks.rb:88:in _run_callbacks' activesupport (4.2.1) lib/active_support/callbacks.rb:776:in_run_call_callbacks'
activesupport (4.2.1) lib/active_support/callbacks.rb:81:in run_callbacks' actionpack (4.2.1) lib/action_dispatch/middleware/callbacks.rb:27:incall'
actionpack (4.2.1) lib/action_dispatch/middleware/remote_ip.rb:78:in call' actionpack (4.2.1) lib/action_dispatch/middleware/debug_exceptions.rb:17:incall'
actionpack (4.2.1) lib/action_dispatch/middleware/show_exceptions.rb:30:in call' railties (4.2.1) lib/rails/rack/logger.rb:38:incall_app'
railties (4.2.1) lib/rails/rack/logger.rb:20:in block in call' activesupport (4.2.1) lib/active_support/tagged_logging.rb:68:inblock in tagged'
activesupport (4.2.1) lib/active_support/tagged_logging.rb:26:in tagged' activesupport (4.2.1) lib/active_support/tagged_logging.rb:68:intagged'
railties (4.2.1) lib/rails/rack/logger.rb:20:in call' actionpack (4.2.1) lib/action_dispatch/middleware/request_id.rb:21:incall'
rack (1.6.1) lib/rack/methodoverride.rb:22:in call' rack (1.6.1) lib/rack/runtime.rb:18:incall'
activesupport (4.2.1) lib/active_support/cache/strategy/local_cache_middleware.rb:28:in call' actionpack (4.2.1) lib/action_dispatch/middleware/static.rb:113:incall'
rack (1.6.1) lib/rack/sendfile.rb:113:in call' railties (4.2.1) lib/rails/engine.rb:518:incall'
railties (4.2.1) lib/rails/application.rb:164:in call' railties (4.2.1) lib/rails/railtie.rb:194:inpublic_send'
railties (4.2.1) lib/rails/railtie.rb:194:in method_missing' passenger (5.0.8) lib/phusion_passenger/rack/thread_handler_extension.rb:89:inprocess_request'
passenger (5.0.8) lib/phusion_passenger/request_handler/thread_handler.rb:155:in accept_and_process_next_request' passenger (5.0.8) lib/phusion_passenger/request_handler/thread_handler.rb:110:inmain_loop'
passenger (5.0.8) lib/phusion_passenger/request_handler.rb:414:in block (3 levels) in start_threads' passenger (5.0.8) lib/phusion_passenger/utils.rb:111:inblock in create_thread_and_abort_on_exception'