4.0.2: crashing terminalserver

Has anyone else encountered a problem with terminalserver in 4.0.2? I'm running a stock standard version of 4.0.2 on some AOpen MiniPCs, booting from CD, and I can't get terminalserver to run. Symptoms: after starting the network (which works fine), and running knoppix-terminalserver, it gets to the call to mkinitrd, and then gives the following messages:
cp: cannot stat `(0xffffe000)': No such file or directory
(repeated 5 times)
cp: cannot stat `/dev/systty': No such file or directory
These didn't worry me _too_ much - looks like a broken script (trying to copy from /dev) rather than something serious.
But then runnfs reports
mv: cannot stat `/etc/exports': No such file or directory
altogether more worrying.

awk then reports that it cannot open /etc/exports-knoppix-terminalserver-orig, again no such file or directory (not surprising, since it couldn't find /etc/exports)
This is reported twice. Then it all culminates in
/etc/init.d/nfs-kernel-server: line 46: mountpoint: command not found
Surprisingnly, after that runnfs appears to terminate normally, but in fact it doesn't appear to be running.
When I try to pxe-boot from another machine, everything goes fine up to the point of mounting the
nfs file system, when (not surprisingly) the boot fails.

It doesn't seem to be corrupt media or anything; I downloaded 4.0.2 again, and md5-ed it, all fine, but it still happens identically with the new CD.

Since I can't see anyone else reporting this problem, it must be something to do with my gear, yet I can't imagine what hardware problem could cause this. Does anyone have any suggestions?