error in rsync protocol data stream

[Ray Lischner]

I am trying to backup an entire disk to a USB-mounted disk, for backup
purposes. Many files are copied, but eventually rsync dies:

$ rsync -axHSv --delete /backup /media/sda1
...
rsync: connection unexpectedly closed (239508 bytes read so far)
rsync error: error in rsync protocol data stream (code 12) at io.c(189)

I am running Suse 9.0 and rsync 2.6.0 on an AMD-K6-2/450 (192MB RAM,
400MB swap). I ran fsck on the source and destination partitions
(ext3), and both are error-free.

Can anyone shed some light on what is going wrong? Thanks.
-- 
Ray Lischner, author of C++ in a Nutshell
http://www.tempest-sw.com/cpp