Hi my friend! I don't recall where, but I have heard that some HP printers share their unix drivers with lexmark printers. By the way, is your lexmark printer running ok with windz?
Let me recommend you something:
1.- Go here:
http://ayo.freshrpms.net/
2.- Download & install the "apts" needed by your distro.
3.-Type: apt-get update then apt-get upgrade
This software should update all your installed programs icluding CUPS
4.- Uninstall your actual printer's configuration, and try again configuring with your upgraded CUPS
I'm wondering if you read/write italian? spanish?
Have a nice time.