I had a different kind of trackpad button failure (mine was stuck as permanently clicked, which prevented booting), but was able to get around it by snipping the cable ''to the button only'' (under the battery). The keyboard and trackpad work as usual, and I turned on trackpad-tap-clicking, which takes some getting used to but works just fine. The one caveat is if you do a reinstall, you'll need to borrow a USB mouse, because the OSX installer doesn't default to tap-clicking.