Selecting a network printer causes a crash

[FridayChild]

I have a MacOSX 10.3 system with an Epson USB printer and an HP Laserjet 4050 printer. The HP is a networked printer and I print to it via IP.
If I print from any application, and the USB printer is selected in the Print menu, and I try to select the network printer from the printer selection drop down menu, the application crashes to desktop.
I have already tried to remove both printers and reinstall them, and to reboot the Mac various times; nothing changed.
If I set the network printer as default, I can print to it, but if I select it from the drop down menu the app crashes.
What can I do?