For most customizations that were available in the vold.conf and rmmount.conf files, you will need to either use Desktop Volume manager preferences or modify the .fdi files.
For rmmount.conf actions, you will need to use either Desktop Volume Manager actions, gconf, or HAL callouts.
Previously, rmmount.conf actions could be run as root on behalf of ordinary users. Now, this is done by installing callout executables in the /usr/lib/hal directory.