Help for managing UIDs on external drive

[Laurent]

Hello,

Can anyone explain, or point me to the documentation,  the process
which mounts a USB key or an external USB hard drive.

I have an external device formatted with ext3. When plugged in, it is
automatically mounted, with respect to files' UIDs, GIDs, etc. The
problem is that those IDs no dot match the running system ones, and
therefore most of the information on the external drive is not
readable.
I'd like to be able, either to have the HD mounted without
consideration of IDs (e.g. my UID/GID for all), or to map the external
device's ID to host system users.

I do not want to change anything on the external HD (e.g. recursive chown).
I have full access to the system (root)

I use Fedora 9, freshly installed 2 weeks ago, not broken yet.

Thank you for any help
Cheers
-- 
-- Laurent