I agree with Bobby on the ssretent here...
By the way, one thing I noticed with volaccess value is that whenever you re-label your volume to another pool, the value will change to the first time you re-labeled that volume to the new pool. So, I don't think that Networker does keep a record when a volume was really first used on your system. Again, this is how what I have observed so far on our system, so please correct me if this is incorrect.
Roose, I think you're getting a little mixed up in the column definitions:
olabel - when the volume was labelled for the first time
labeled - the most recent time the volume was labelled (or re-labelled)
volaccess - last time volume was accessed for read or write
It is the olabel value that shouldn't change. I haven't tested this though. Are you seeing this value changing?