1.621: Why does my 64 port concentrator loose data and drop the queue?

This problem has been associated with upgrading machines to 3.2.5.
Try changing the values for the "Transmit buffer count" parameter in
the printer/plotter setup in smit. You need to experiment with this
parameter, to see which value that makes the printer print as fast as
possible.  If the value is too high, the printers will loose some of
the data, and the queue will be disabled.  If the value is too low,
the printers will print very slowly.