When I asked Mike Sterling (of Casady & Greene) about this, he informed me that it was related to Eudora's "Esoteric Settings v3.1" file - especially the one labeled "Really Miscellaneous." He writes: "In that Settings panel, there is a toggle switch for "Faster Typing." Make sure that switch is disabled. According to Evan Gross, the programmer of Spell Catcher: 'Beware any applications with this sort of setting. It bypasses the normal event getting mechanism for speed purposes, and Spell Catcher doesn't see all the keystrokes.'"