I have a Perfection 1250, and both the Epson Scan to File & Epson Twain 5 work fine in Panther (Epson says they're for OSX 10.2~10.2.8).
Did you install the Twain driver? If you have it installed try launching Image Capture (OSX/Applications/Utilities) and scanning from there.
If that works you know it's not a hardware issue. In general, using TWAIN from inside another application (Apple Image Capture; PhotoShop; Graphic Converter, etc) works best with Epson scanners and OSX.