unexplained error (code 130) at rsync.c(271)

[Martin Magnusson]

I'm using rsync 2.6.9 and rsnapshot 1.2.9 on Ubuntu 8.04. When using
rsnapshot to backup a remote computer over ssh, I get the message

rsync error: unexplained error (code 130) at rsync.c(271) [generator=2.6.9]
ERROR: /usr/bin/rsync returned 130 while processing root at undertow:/

I looked at the source for rsync 2.6.9, and line 271 in rsync.c is just
a comment. Furthermore, it is in the function void finish_transfer(), so
I don't see how it could return 130.

Does anybody know in which cases rsync might return 130, and what it means?