Personal LW NTR: Postscript and Setting Tray Defaults

I'm getting a PostScript error when trying to set the paper tray format in the
A4 paper tray. I'm using a SUN Workstation with UNIX and a Personal LaserWriter
NTR.

When I print documents from the A4 tray, the printer driver uses a
"Letter" format and margins are different.

This is the PostScript code I'm using:

%! /str 60 string def statusdict begin 60
defaultmultipurposepapertraysize str cvs print job end ( ) print
statusdict begin 60 defaultmultipurposepapertraysize pop str cvs print
end servedict begin O exitserver statusdict begin a4 true
defaultmultipurposepapertraysize end

The operators for returning and setting the default multipurpose tray
paper size are spelled incorrectly in the "Personal LaserWriter NTR
Printer Developer Note". The correct spellings, respectively, are:

defaultmultipurposetraysize

and

setdefaultmultipurposetraysize

This PostScript code will print a page showing the default
multipurpose tray paper size:

/Times-Roman findfont
15 scalefont
setfont
72 700 moveto
/str 20 string def
(Default multipurpose tray paper size: ) show
statusdict begin
defaultmultipurposetraysize pop str cvs show
showpage

This PostScript code changes the default multipurpose tray paper size
based on the values used for "NAME" and "BOOL":

serverdict begin 0 exitserver
statusdict begin
NAME BOOL setdefaultmultipurposetraysize

The allowable values for "NAME" are the standard device setup procedures:

/letter
/legal
/a4
/b5

The standard device setup procedures /lettersmall and /a4small are not
allowed.

The "BOOL" parameter is included for compatibility with other PostScript
printers. It specifies whether the paper is to be fed long edge first or
short edge first. For all paper sizes on the Personal LaserWriter NTR, the
value of "BOOL" must be true, meaning short edge first.

The following PostScript code changes the default multipurpose tray paper
size to a4:

serverdict begin 0 exitserver
statusdict begin
/a4 true setdefaultmultipurposetraysize