mapping not compatible

metacpan@lw-mc-01:~/metacpan-api$ ~/bin/metacpan-api-carton-exec ./bin/metacpan mapping

2016/03/30 19:43:36 I mapping: Putting mapping to ElasticSearch server
[Request] ** [http://127.0.0.1:9200]-[400] [mapper_parsing_exception] Mapping definition for [_timestamp] has unsupported parameters:  [store : 1], called from sub Search::Elasticsearch::Transport::perform_request at /home/metacpan/carton/metacpan-api/lib/perl5/ElasticSearchX/Model/Role.pm line 51. With vars: {'request' => {'ignore' => [],'qs' => {},'body' => {'session' => {'_timestamp' => {'store' => 1,'enabled' => 1},'properties' => {},'dynamic' => \0}},'serialize' => 'std','mime_type' => 'application/json','path' => '/user/session/_mapping','method' => 'PUT'},'status_code' => 400,'body' => {'error' => {'type' => 'mapper_parsing_exception','root_cause' => [{'type' => 'mapper_parsing_exception','reason' => 'Mapping definition for [_timestamp] has unsupported parameters:  [store : 1]'}],'reason' => 'Mapping definition for [_timestamp] has unsupported parameters:  [store : 1]'},'status' => 400}}