HELP in XENIX/Altos problem

[tm at laidbak.UUCP]

The following is a problem a friend overseas faces. His system is
XENIX version 3.3aSO and runs on an Altos 2086. Everything seemed to be
working fine until they hooked up a CDC 9335-2 printer to the parallel port.
The problem occurs intermittently, under various conditions:
printing single page documents, multi-page documents, and regardless the
program used to print. The following appear in the console:

lp: cannot get a page
lp: cannot get a page
lp: cannot get a page
	...
TRAP 000D IN SYSTEM

ax=FFFE bx=FFFE cx=0028 dx=0128
si=7FFF di=0001 bp=0380
fi=0206 uds=0018 es=0128
pc=0020:B39C Ksp=036A

The lp log file /usr/spool/lpd/LOGFILE contains then messages:

TIME AND DATE OF CRASH	WHAT HAPPENED	      DEVICE		 WHO DID IT
Mon Nov 24 1:35:11:lpd:Cannot reopen stdin as /dev/lp 0 bytes printerr joe

The local CDC (they support Altos) people have made a cable of their own
to connect the printer to Altos, and they suspect that this might be the
problem.
It seems obvious that these panic messages come out of the lp device driver,
but they do not have the sources and cannot verify it.
Does any kind soul out there know what really happens?
Could it be something like a cold soldering connection in the cable?
Could somebody please give me info on how to get in touch with Altos to buy
the original cable of Altos just in case?
Any help greatly appreciated.

	-Takis Mercouris
	ihnp4!laidbak!tm