Broken pipe error in local copy mode

[Steve]

I get an error when copying a specific directory using rsync. It works for a lot of smaller files, but when it comes to a 1.2 GB file, it always fails with the following error:

  rsync: writefd_unbuffered failed to write 4 bytes: phase "unknown": Broken pipe
  rsync error: error in rsync protocol data stream (code 12) at io.c(515)

I've read at several places that this is an error which seems to occur for more users in connection with network transfer and full hard disks. But in my case, this is a local-to-local copy (no remote paths involved), where there is plenty of space (approx. 10 times of the amount I want to copy) on the target disk.

I use rsync 2.5.6 on a RH8 based Linux 2.4.21 system.
The command options I've been using are the following:
  rsync --archive --one-file-system /export1/ /export2/
where /export1 and /export2 are separate hard disks with plenty of space on /export2

Can anyone give me a hint what the problem could be here?

Thanks,
Steve