HP 870 Cse + HPIJS 2.14 Printer Driver does not support two-sided print

I have installed and used an HP Deskjet 870 Cse printer for
some time, but find that the I/F for using it is rather limited
by comparison with that available for Windows. I searched the
web, and found the "HP printer home page" on SourceForge. I downloaded
the most recent version of HPIJS (recommended for this printer)
and installed it successfully just now. The latest version
is dated August 2005. I am still missing several features which
this printer/driver combination supposedly supports. I am
particularly interested in two-sided printing and two-up
printing.

I would like to access these features from, for example,
Mozilla using the File->Print. This brings up a dialogue
box which has features like margins, and grey-scale
rendering, but nothing about two-sided printing etc.

Further googling with '+"two sided printing" +linux'
produced many hits, but not much help. This printer
does not support duplexing, but I have used it with
a driver for Windows which prints the even pages, then
the odd pages, with a pop-up dialogue window prompting
for page reversal.

Searching the HP website produced lots of information about
the printer, but not much help in configuring it with
Linux.

Information which may help:

$ which hpijs
/usr/local/bin/hpijs
$ hpijs -h


Hewlett-Packard Co. Inkjet Server 2.1.4
Copyright (c) 2001-2004, Hewlett-Packard Co.
$ uname -a

The test page states at the bottom:

Printed Using CUPS v1.1.x
Copyright 1993-2003 by Easy Softwre Products, All Rights Reserved

Would someone please give me pointers for further research?

Thank you for your time in reading this message.

Mike
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