My problem is the following (Ubuntu 9.04):

When I insert a usb key, it doesn't automount (as it did before) because there is a "wrong mount option" (this is what the error message says). I know why this happens: because the last time it was automounted, I changed an option and made a mistake, so since I unmounted it, I wasn't be able to automount it again.

I know can mount it in different ways, but I just want to recover the correct functioning of the automount option. So my question is: where are these options saved? How can I change them?

Thanks very much