Notification Emails (logs) not consistent / complete

My nightly incremental backups appear to run fine, but the notification emails and log entries are missing info. When I first set the backups up, email notifications included good info:

12 Information 11/19/2010 9:00:14 PM Locking partition D:...
13 Information 11/19/2010 9:00:15 PM Create Incremental Backup Archive From: My Data To file: "\\NAS02\BACKUPS\JIM\CENTURION\FILE BACKUPS\CenturionDataFiles526.tib" Compression: High
14 Information 11/19/2010 9:12:56 PM Operation has succeeded.

After the backups ran for several days, the notifications stopped containing file information. Perhaps a bug introduced along the way? Here's what I see now:

12 Information 11/27/2010 9:00:28 PM Locking partition D:...
13 Information 11/27/2010 9:00:29 PM Create Incremental Backup Archive From: My Data To file: "" Compression: High
14 Information 11/27/2010 9:05:16 PM Operation has succeeded.

Any thoughts? I'm stumped.