zs1 parity error on 3/180 sunos 4.1

[Per Foreby]

I keep getting the following line on a sun 3/180 running 4.1:

	vmunix: zs1: parity error ignored

The console is a terminal plugged into a serial port, so zs1 isn't really
used. In fact, I have excluded the support for zs1 from the kernel.

Anyone knows what causes this behaviour? 

Per Foreby					Email: perf at efd.lth.se
System manager at EFD, Lund Institute of Technology (Lund University)
Snail: E-huset, LTH, Box 118, S-221 00 LUND, Sweden. Phone: +46 46 107492