Allow a user to edit smart variable

Hi,

i'm trying to allow some users to edit a spécific smart variable.
I've created a role wirh a filter on the resource Lookup Key with the
permissions view_external_variables and edit_external_variables, and a
search string which match my smart variable.
When I login with a test user, I can only see my smart variable, that's ok.
But when i click on it to edit I have the message "LookupKey Not Found".
With the debug, i can see that foreman is using this mysql request :
SELECT DISTINCT filters.* FROM filters INNER JOIN filterings ON
filterings.filter_id = filters.id INNER JOIN permissions ON
permissions.id = filterings.permission_id INNER JOIN roles ON
filters.role_id = roles.id INNER JOIN cached_user_roles ON
roles.id = cached_user_roles.role_id LEFT JOIN taxable_taxonomies
ON (filters.id = taxable_taxonomies.taxable_id AND taxable_type = 'Filter')
LEFT JOIN taxonomies ON (taxonomies.id = taxable_taxonomies.taxonomy_id)
WHERE cached_user_roles.user_id = 7 AND (permissions.resource_type =
'LookupKey') AND (permissions.name = 'edit_lookup_keys') AND
(taxable_taxonomies.id IS NULL OR (taxonomies.type = 'Organization') OR
(taxonomies.type = 'Location')) ORDER BY role_id, filters.id

I understand that it is searching for a permission called 'edit_lookup_key'
but it doesn't exist at all in the permissions table, so i can't give this
right to my user !
Do I have to manually create that entry in mysql ?