Parallel port not found

[Marc Joigny]

Hello.
I am using Ubuntu 7.04 with the 2.6.20-15 kernel without any trouble with parallel port recognition, it is working very well.
I have switched to Ubuntu 9.04 (2.6.28 kernel) for something more modern and when I have tried to configure printing, Cups did not detect my old HP DJ 710C connected to parallel port.
It detected successfully the 2 serial ports and gave network options, but no more my good old parallel port.
Believing something had died on my hardware, I have switched back to Ubuntu 7.04 and printing is still fine.
Following a tip from a friend, I have tried on 9.04
lsmod [ grep partport (+ lp)
and got :
dad at dad-desktop:~$ lsmod | grep parport
parport                42220  2 ppdev,lp
dad at dad-desktop:~$ lsmod | grep lp
lp                     17156  0
parport                42220  2 ppdev,lp
So, the parallel port is here.
Do you know where is located the config file?
I have searched, found and printed cupsd.conf on 7.04, found it on 9.04, but it seems they are examples.
The problem is the same with recent distros like Slackware 12(using 2.6.21.5 kernel) and Kubuntu 9.04 (same kernel as Ubuntu 9.04).
I have a bunch of old printers still very healthy and would really like to go on using them.
I am in a LUG in France and we are trying hard to persuade people to switch to Linux, especially on old machines and would like not to disapoint them.
Who might help?
Thank you for tips.
Yours sincerely
Marc Joigny Linux convert since 2004