I get the following error during a "make release" on NetBSD-1.5C/i386
building with sources from 20000903:

all ===> i386/floppies/fdset
rm -f netbsd
cp /usr/obj/usr/src/distrib/i386/floppies/ramdisk-kernel/netbsd.INSTALL.gz netbsd
rm -f boot
cp /usr/obj/NetBSD/usr/mdec/biosboot.sym boot
strip boot
tar cvf ustar.tmp boot netbsd
boot
netbsd

Making disk number one
mv -f boot1.fs boot1.fs.tmp
mv: rename boot1.fs to boot1.fs.tmp: No such file or directory
*** Error code 1 (ignored)
dd if=/dev/zero of=boot1.fs.tmp count=2880
2880+0 records in
2880+0 records out
1474560 bytes transferred in 1 secs (1474560 bytes/sec)
vnconfig -t floppy3 -v -c /dev/vnd0d boot1.fs.tmp
/dev/vnd0d: 1474560 bytes on boot1.fs.tmp using geometry 512/18/2/80
dd bs=8k seek=1 count=179 if=ustar.tmp of=/dev/vnd0d
179+0 records in
179+0 records out
1466368 bytes transferred in 1 secs (1466368 bytes/sec)
disklabel -rw /dev/vnd0d floppy3
installing new bootblocks
/usr/obj/NetBSD/usr/mdec/installboot -b 17 -v -f /usr/obj/NetBSD/usr/mdec/biosboot.sym /dev/rvnd0a
/usr/obj/NetBSD/usr/mdec/biosboot.sym: entry point 0x805d000
proto bootblock size 49152
room for 10 filesystem blocks at 0x578
installboot: not enough fragment space in bootcode

/dev/rvnd0a: block number 17, size 41472 table blocks: 11/10
*** Error code 1

Stop.
*** Error code 1

Stop.
*** Error code 1

Stop.
*** Error code 1

Stop.
*** Error code 1

Stop.