Rosetta crashes in +translate because of a foreign key constraint error in posubmission

[Christian Reis]

From OOPS-59A359:

ProgrammingError: ERROR: insert or update on table "posubmission" violates foreign key constraint "posubmission_pomsgset_fk" DETAIL: Key (pomsgset)=($INT) is not present in table "pomsgset". INSERT INTO POSubmission (id, origin, pluralform, validationstatus, person, pomsgset, potranslation, datecreated) VALUES ($INT, $INT, $INT, $INT, $INT, $INT, $INT, CURRENT_TIMESTAMP AT TIME ZONE $STRING)

Not sure how this happens, yet.