This is on debian (mostly etch)

When I connect an USB stick it immediately gets mounted to /media/xxx.
It seems like udev first notices the event and passes it on to hald,
because this no longer happens when I stop either udev or hald (dbus).

Why is this a problem to me?

(1) I don't undestand what is going on. I cannot figure out how and why
hald tries to mount the USB device. Furthermore I don't undetstand what
ivman does in this context. It seems to me that all these programs
(udev, hald, ivman, hotplug and additionally some kde/gnome programs)
can automatically mount and unmount devices.

(2) I cannot unmount the USB stick from the Thunar file manager. When I
umount /dev/sda *manually* and then click on the "128 MB removable
medium" in Thunar, it mounts /dev/sda and I can unmount it from Thunar
just fine. But when udevd, hald or whoever mounts it FIRST, then Thunar
can no longer unmount it.

(Is there a recmommended ("least-messy") way of setting up or using