Sorry to bump an older thread, but I'm also in the situation of having a library of old eReader.com books from Palm days. I just picked up the Nook Tablet and sideloaded the eReader.com Android app. It does work and opens the books, but it won't fill the screen as it appears to have been designed for phones.
Very tiny on the Tablet and might as well stick to the iPhone.
Has anyone been able to solve this or is this something that must be lived with if I don't want to remove the drm?