It is API v2, excerpt from server log attached. It was not spotted when filtered by host, hostgroup or env

Started GET "/api/puppetclasses/9/smart_class_parameters" for 127.0.0.1 at 2013-11-15 13:52:58 +0100
Processing by Api::V2::SmartClassParametersController#index as JSON
Parameters: {"puppetclass_id"=>"9", "smart_class_parameter"=>{}}
.....
Rendered api/v2/smart_class_parameters/index.json.rabl (170.0ms)
Body: {"smart_class_parameters":[{"parameter":"sat6_baseurl","id":22,"description":"","override":false,"parameter_type":"string","default_value":"${$sat6::params::sat6_baseurl}","required":false,"validator_type":null,"validator_rule":null,"override_value_order":"fqdn\nhostgroup\nos\ndomain","override_values_count":0,"created_at":"2013-10-09T11:59:37Z","updated_at":"2013-10-09T12:00:32Z","override_values":[],"environments":[{"environment":{"id":2,"name":"development"}},{"environment":{"id":3,"name":"testing"}}]},{"parameter":"sat6_baseurl","id":22,"description":"","override":false,"parameter_type":"string","default_value":"${$sat6::params::sat6_baseurl}","required":false,"validator_type":null,"validator_rule":null,"override_value_order":"fqdn\nhostgroup\nos\ndomain","override_values_count":0,"created_at":"2013-10-09T11:59:37Z","updated_at":"2013-10-09T12:00:32Z","override_values":[],"environments":[{"environment":{"id":2,"name":"development"}},{"environment":{"id":3,"name":"testing"}}]},{"parameter":"sat6_version","id":20,"description":"Sat6 Compose","override":true,"parameter_type":"string","default_value":"MDP2-S7-C1","required":true,"validator_type":"","validator_rule":"MDP2-S4-C3, MDP2-S4-C4, MDP2-S5-C1","override_value_order":"fqdn\nhostgroup\nos\ndomain","override_values_count":0,"created_at":"2013-10-07T09:24:50Z","updated_at":"2013-11-11T14:16:15Z","override_values":[],"environments":[{"environment":{"id":2,"name":"development"}},{"environment":{"id":3,"name":"testing"}}]},{"parameter":"sat6_version","id":20,"description":"Sat6 Compose","override":true,"parameter_type":"string","default_value":"MDP2-S7-C1","required":true,"validator_type":"","validator_rule":"MDP2-S4-C3, MDP2-S4-C4, MDP2-S5-C1","override_value_order":"fqdn\nhostgroup\nos\ndomain","override_values_count":0,"created_at":"2013-10-07T09:24:50Z","updated_at":"2013-11-11T14:16:15Z","override_values":[],"environments":[{"environment":{"id":2,"name":"development"}},{"environment":{"id":3,"name":"testing"}}]}]}
Completed 200 OK in 302ms (Views: 130.4ms | ActiveRecord: 103.7ms)

My guess is that group by is missing envs, but may just be coincidence..