I don't know if this will help you, http://wiki.archlinux.org/index.php/HAL#HAL_and_hotplugging . You have probably already read through it, but I had a problem yesterday and someone suggested reading this. I ended up using fstab, instead of HAL.
I don't know if you need a line in fstab? It seems you know more about this stuff then me though, ;-). Also, http://wiki.archlinux.org/index.php/Udev , http://wiki.archlinux.org/index.php/HAL#USB_sticks_and_drives_do_not_automount_correctly . http://bbs.archlinux.org/viewtopic.php?pid=248224 . Hope this helps.
