I did
apt-get install cupsys cupsys-bsd cupsys-client cupsys-driver-gutenprint hpijs

ps aux | grep cups
root 1513 0.0 0.0 1948 624 pts/6 R+ 12:03 0:00 grep cups

apt-cache policy cupsys
cupsys:
Installed: 1.1.23-12
Candidate: 1.1.23-12
Version Table:
*** 1.1.23-12 0
500 ftp://ftp.se.debian.org testing/main Packages
500 ftp://ftp.hu.debian.org testing/main Packages
500 ftp://ftp.debian.org testing/main Packages
100 /var/lib/dpkg/status
1.1.23-10sarge1 0
500 ftp://ftp.se.debian.org stable/main Packages
500 ftp://ftp.hu.debian.org stable/main Packages
500 ftp://ftp.debian.org stable/main Packages
500 ftp://security.debian.org stable/updates/main Packages


tail -n 20 /var/log/cups/error_log
hebrews:/home/epjh# tail -n 20 /var/log/cups/error_log
E [14/May/2006:06:57:23 -0400] LoadAllPrinters: Unable to open /etc/cups/printers.conf - No such file or directory
E [14/May/2006:06:57:23 -0400] LoadAllClasses: Unable to open /etc/cups/classes.conf - No such file or directory
I [14/May/2006:06:57:24 -0400] LoadPPDs: Read "/var/lib/cups/ppds.dat", 799 PPDs...
I [14/May/2006:06:57:24 -0400] LoadPPDs: No new or changed PPDs...
I [14/May/2006:06:57:24 -0400] Full reload complete.
E [14/May/2006:06:57:24 -0400] StartListening: Unable to bind socket for address 00000000:631 - Address already in use.
E [14/May/2006:11:55:43 -0400] Unknown directive warn on line 160.
I [14/May/2006:11:55:43 -0400] Listening to 0:631
I [14/May/2006:11:55:43 -0400] Listening to 0:631
E [14/May/2006:11:55:43 -0400] Unknown directive @LOCAL on line 567.
I [14/May/2006:11:55:43 -0400] Loaded configuration file "/etc/cups/cupsd.conf"
I [14/May/2006:11:55:43 -0400] Configured for up to 100 clients.
I [14/May/2006:11:55:43 -0400] Allowing up to 100 client connections per host.
I [14/May/2006:11:55:43 -0400] Full reload is required.
E [14/May/2006:11:55:43 -0400] LoadAllPrinters: Unable to open /etc/cups/printers.conf - No such file or directory
E [14/May/2006:11:55:43 -0400] LoadAllClasses: Unable to open /etc/cups/classes.conf - No such file or directory
I [14/May/2006:11:55:44 -0400] LoadPPDs: Read "/var/lib/cups/ppds.dat", 799 PPDs...
I [14/May/2006:11:55:44 -0400] LoadPPDs: No new or changed PPDs...
I [14/May/2006:11:55:44 -0400] Full reload complete.
E [14/May/2006:11:55:44 -0400] StartListening: Unable to bind socket for address 00000000:631 - Address already in us

hebrews:/home/epjh# lsof -i TCP:631
hebrews:/home/epjh#

I would check something like "nmap localhost", I know you already used lsof but this may turn something up.
A work around may be to edit your /etc/cups/cupsd.conf file. Add the line:

Listen localhost:632
or try:
Port 632

This will switch cups to a new port then check locahost:632 from your web browser.

hebrews:/home/epjh# nmap localhost

Starting Nmap 4.00 ( http://www.insecure.org/nmap/ ) at 2006-05-15 16:07 EDT
Interesting ports on localhost (127.0.0.1):
(The 1662 ports scanned but not shown below are in state: closed)
PORT STATE SERVICE
9/tcp open discard
13/tcp open daytime
22/tcp open ssh
25/tcp open smtp
37/tcp open time
80/tcp open http
111/tcp open rpcbind
113/tcp open auth
960/tcp open unknown
5432/tcp open postgres

Nmap finished: 1 IP address (1 host up) scanned in 0.135 seconds

I tried changing to Port 632; and the connection was still refused.

Are you using iptables or xinetd?

I ma using iptables.