Hi! Hmm, found a neat programm which could tell you if the card is on the pci bus: lspci or so from the package pciutils. Please try that once. And... you could try the following module parameter: esstype=0 (and nothing more). Another question: Have you compiled the kernel yourself, and which system are you running (testing=sid or stable=potato or unstable=woody)? If you have CD's, it's probably potato.
Cheers, Stephan