Mac OS X Panther includes many Epson printer drivers, but they're not all installed by default. You can easily install one you need if Printer Setup Utility doesn't list your printer under EPSON USB, EPSON FireWire, EPSON AppleTalk, or EPSON TCP/IP.
Document 25588, "Mac OS X 10.3: Raster (Inkjet) Printer Drivers Included", lists all Epson inkjet printer drivers included with Mac OS X 10.3 Panther.
Note: Printer drivers included in the Epson Printer Drivers 1 package are installed by default. Drivers included in the Epson Printer Drivers 2 package are not. If your driver isn't installed, it's probably in the Drivers 2 package or not included with Mac OS X Panther. If it's not included, see if it's available from Epson's website (http://www.epson.com/). Later versions of printer drivers, even ones included with Mac OS X Panther, may be available there, too.
Follow these steps to install an Epson driver from the Epson Printer Drivers 2 package: