Sorry for all my messages, but it looks like 3.1.03 should fix this.
Here's the info I found:

IX75602 - When backing up or archiving from a Version 3 client to a
Version 2 server directly to offline media, a few files may not be backed
up or archived if retries are needed, even though ADSM reports that they
are backed up or archived, with no error messages

Just posting it for anyone else who isn't aware of this problem. I'll post
another message with the results of applying this PTF.

Sorry again for the many messages!

Thanks,
-Scott
________________________________________________________________________
________________________________________________________________________
    L. Scott Emmons    | CableData R&D Center - El Dorado Hills, CA, USA
Staff Software Engineer|   Special Projects, Systems Development Dept
    (916) 939-6088     |  Views and content are my own, not CableData's