BU2012 D2D Backup FileServer with PST's
We are testing BUExec 2012, we currently run 2010, against other D2D backup solution providers. One of our issues has been backing-up PST's that reside on our file servers. Currently we have between 600-700GB of PST's. The problem in the past has been the user opens and saves to the PST daily and the backup software will backup the entire file instead of the byte level changes to the file on a daily basis when running our differentials. I just tested 2012 and on day 1 my test PST was 11mb in size and it was backed-up accordingly. On the moring of day 2 I added 20MB of mail to the PST and that was the only change I made to our test datastore. That evenings differential backup was 31MB in size which obviously represented the backup of the entire PST.
We replicate the the disk datastore to a remote location for DR purpose and we would not be able to re-replicate 6-700GB a night.
Is there a way to setup 2012 D2D to only perform byte level differential of our PST's, or for that matter any other data?