I have a laserjet 4L SMB printer (on a windows machine) that worked well in RH8, but in RH9 it only prints the top left quarter of each page, scaled to fit the whole page. I tried to remove the queue and re-add it. But that made no difference. I use the ljet4 driver. Resolution is listed as 300 DPI in r-c-p, but changing it to 150 DPI doesn't help.
Does this happen with the test page, or only when printing from other applications? Assuming you are using CUPS, please enable debugging by editing /usr/lib/cups/filter/cupsomatic and setting the debug variable to '1'. Alternatively, for LPRng, edit /usr/sbin/lpdomatic and make the same change. After printing you should get some debugging information in /tmp.
I switched from LPng to CUPS, and now it works fine.