Firefox 1.5 printing problems on Solaris

I am using Firefox 1.5 on a Solaris 9 system.  I am having problems
printing using the xprint system to my HP LaserJet 4M PostScript printer.
In general the printing works.  I can perform a print preview and
everything looks fine, but when I send output to the printer, the text
often runs off the right side of the page and is lost.  I'm pretty sure
the problem has to do with font mapping, as the output appears differently
from what I see in the print preview and I'm guessing that the font
substitutions taking place throw off the rendering engine which expects
the printed output to match the print preview.

I have checked the printer setup and everything appears to be fine.  The
paper is set to na-letter and sizes are 215x279 mm (8.5x11 inches) with
0.5" margins all sides and print_edge set to 4mm all sides.  The default
font is set to 12pt adobe-helvetica-iso8859-1 which is the same setting for
Serif and Sans-serif.  The Monospace font is 12pt -courier-iso8859-1.

I have the same version of Firefox running under Windows XP on my
SunPCi-III card and, with the same settings it prints properly.

Any suggestion as to what is wrong and how to correct it?

Also, any idea why the Page Setup menu shows my margins in inch increments
on my Windows system but displays them in millimeters on the Solaris
system?  Is this something that was compiled into the Firefox build or can
this be changed?

Thanks!
-- 
Jeffery Small