pb executing procedure in a package

Being user 'JOHN' I declare and implement a package 'PKG' having a procedure 'PROC'. I don't understand why I can't run my function as : JOHN.PKG.PROC (the name of the package is qualified by the name of the schema), using PKG.PROC works or, connected as an other user, running JOHN.PKG.PROC is ok (as expected).

Actually my motivation is to setup a access policy using the package DBMS_RLS but I've been unable to enable a policy in a schema using a procedure belonging to the same schema.

Thank you,

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Jean-Paul Le Fèvre * CEA Saclay DAPNIA/SEI * Jean-Paul.LeFevre_at_cea.fr