The Quadra 950 running A/UX 3.0 using the System V spooler (lp) to a serial printer has the same problem that the Macintosh IIfx had running A/UX 2.0.
As with the Macintosh IIfx, you must use the Serial Switch (1.1) set to
compatible mode to succesfully use the System V spooler on the Quadra.
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