H P Printers are known to be Linux friendly, thats why I switched to H P from Lexmark, anyway, have you loaded the hpjs drivers, they are on your mandrake disks. I am using a HP Photosmart 7350 as a network printer and it is working fine. Also go to" linuxprinting.org" and there is a place where you can put in your printer make and model and it will tell you if it's compatable with Linux, I checked there before I bought mine.If you can't locate that hpjs driver on your disks post back and I"ll try to find a better description for you .Hope this helps.
I just checked the linuxprinting.org site and it says you need the foo2zjs driver and they have a link on the site for it. heres the page I looked at
http://www.linuxprinting.org/show_printer.cgi?recnum=HP-LaserJet_1000