Hi Gordon!
I have the same problem but with a brekdown at about 2,2 GB. I also used a W2K (yes NTFS) machine with 40GB Harddisk and IE5.5 to perform a desktop backup.
Did I understand that right: with Netscape your backup worked fine ? Because I think the explorer is the Problem when building an output file from an http download bigger than, in my case 2,2G
A fiend of mine thinks "that Linux ist the problem case it cnt handle files bigger then 2GB. So wehn you perform a Backup e-smith has to build an output file wich is downloaded by the browser."
I am only medium skilled linux user so I am not sure if this is correct.
I switched to Norton Ghost 6.5 to make full backups, because you can make them on harddisk and mulitple CD.

Not useabel for upgrade backups

So I am still very interested to solve this problem.
WL