ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-release-1-6/tar_files/src/rescue.tar.gz
is only 20 bytes in size and doesn't contain a valid tarball.

ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-current/tar_files/src/rescue.tar.gz
is 1,940 bytes in size and does contain a valid tarball.

The file sizes are different enough to make clear 1-6-RELEASE and current are
definitely different variants.  I'm guessing the "src/rescue" directory isn't
used in 1-6-RELEASE and "rescue.tar.gz" should be ignored.  If that's true,
please delete "rescue.tar.gz" from "NetBSD-release-1-6/tar_files/src".

I don't subscribe to "netbsd-bugs@netbsd.org" so please email me directly if
you need my attention.

TIA,

Conrad