Error after upgrade to NetBSD 5.1

[Tobi Schäfer <interface%p3k.org@localhost>]

Hello.

I am trying to install NetBSD 5.1 on a Performac 475 w/ upgraded FPU. I was 
running 1.6 for a long time (10 years or so) and now wanted to see what 
happened in NetBSD land in the meantime.

So I downloaded the sets and followed the instructions for the traditional 
installation, using the NetBSD Installer app running from System 7.

(Using sysinst does not seem to be an option because I do not have a CD-Rom 
drive.)

The next day the installation was finished and I finally selected the Build 
Devices command from the Installer app’s menu and booted into NetBSD afterwards.

I can see the new kernel is loading and then I am prompted:

   Enter pathname of shell or RETURN for /bin/sh: 

But when I enter return, I get the following error:

   -sh: Undefined PLT symbol "__stat30" (symnum = 55) 

So, my questions are: 

1. Is NetBSD 5.1 running on my Mac, anyway?
2. If not, which version should I try?
3. Did I take the right steps for updating?
4. If not, how am I supposed to update the installation?
5. What should I do next?

Would be very glad to get some help.

Cheers,
Tobi