color printing with Stylus 800

I have a Stylus 800 and used apsfilter to setup a /etc/printcap. For the ghostscript conversion, I am using
the st800 driver. The problem is that all printjobs are
printed correctly, but colors are always printed in black
& white, even if I specify lp4 on the command line:

lpr -Plp4 <color.picture>

My printcap looks as follows:

# LABEL apsfilter
# apsfilter setup Fri Dec 11 13:55:19 CST 1998
#
# APS_BASEDIR:/usr/local/lib/aps
#
#
ascii|lp1|st800-letter-ascii-mono|st800 ascii mono:\
        :lp=/dev/lp0:\
        :sd=/usr/spool/st800-letter-ascii-mono:\
        :lf=/usr/spool/st800-letter-ascii-mono/log:\
        :af=/usr/spool/st800-letter-ascii-mono/acct:\
        :if=/usr/local/lib/aps/filter/aps-st800-letter-ascii-mono:\
        :mx#0:\
        :sh:
#
lp|lp2|st800-letter-auto-mono|st800 auto mono:\
        :lp=/dev/lp0:\
        :sd=/usr/spool/st800-letter-auto-mono:\
        :lf=/usr/spool/st800-letter-auto-mono/log:\
        :af=/usr/spool/st800-letter-auto-mono/acct:\
        :if=/usr/local/lib/aps/filter/aps-st800-letter-auto-mono:\
        :mx#0:\
        :sh:
#
lp3|st800-letter-ascii-color|st800 ascii color:\
        :lp=/dev/lp0:\
        :sd=/usr/spool/st800-letter-ascii-color:\
        :lf=/usr/spool/st800-letter-ascii-color/log:\
        :af=/usr/spool/st800-letter-ascii-color/acct:\
        :if=/usr/local/lib/aps/filter/aps-st800-letter-ascii-color:\
        :mx#0:\
        :sh:
#
lp4|st800-letter-auto-color|st800 auto color:\
        :lp=/dev/lp0:\
        :sd=/usr/spool/st800-letter-auto-color:\
        :lf=/usr/spool/st800-letter-auto-color/log:\
        :af=/usr/spool/st800-letter-auto-color/acct:\
        :if=/usr/local/lib/aps/filter/aps-st800-letter-auto-color:\
        :mx#0:\
        :sh:
#
raw|lp5|st800-letter-raw|st800 auto raw:\
        :lp=/dev/lp0:\
        :sd=/usr/spool/st800-raw:\
        :lf=/usr/spool/st800-raw/log:\
        :af=/usr/spool/st800-raw/acct:\
        :if=/usr/local/lib/aps/filter/aps-st800-letter-raw:\
        :mx#0:\
        :sh:

What do I need to do to get the printer to start printing in color?

Thanks for any help.