you may have to reconfigure
You may have to reconfigure the printer. Add the printer in the system setting. make sure the printer is connected and On(Once i struggled why its not detected and the cable was loose!!). In the setting you could select the correct driver and it'll work from then on. After upgrade somehow your old setting may have disappeared. Although my printer was a samsung one. In etch i think some special software is also there for hp printers. Try seeing that too.
i use in kde open the printing configuration tool, set printer as local one on parallel port/usb and on prompting select the printer driver.