You're welcome. Basically, a given printer event is unique by
combining 'printer-uri', 'subscription-id', ['job-id'], and
'request-id' (the sequence number).
A given job event is unique by combining all four of the above
(although the particular 'subscription-id' in the collection
on the job may be of less interest to the client than in the
printer event case above.
- Ira McDonald
High North Inc