how to script duplex printing

[Kevin O'Gorman]

I have a little script that makes Postscript from man pages.  I
sometimes like to print these.  I used to use
  manlp <something> | lpr
and it worked fine.  However, I now have a printer capable of
duplexing, but to use that feature, I have to
  manlp <something> | ps2pdf ><somewhere>
  evince <somewhere>
and tell the printer driver used by evince to duplex its output.

Is there some way to script this, preferably in a single pipeline?

-- 
Kevin O'Gorman, PhD