I know this is a topic a lot of people are interested in. How
to get udev hotplugging working. It's not a simple procedure,
but I got it to work on a Sparc so it should work for everyone.

First off, you will need to patch the kernel. 2.6.15 is not all
the way there, but GregKH has the necessary patches available to
make it work. I used

http://www.kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/old/gregkh-all-2.6.15.patch

Second, you will need to use udev 079, here is the build instructions
you must use to get full functionality.
make EXTRAS="extras/firmware extras/scsi_id extras/volume_id extras/ata_id extras/usb_id extras/edd_id extras/dasd_id extras/cdrom_id extras/floppy" udevdir=/dev

make EXTRAS="extras/firmware extras/scsi_id extras/volume_id extras/ata_id extras/usb_id extras/edd_id extras/dasd_id extras/cdrom_id extras/floppy" udevdir=/dev install
cp extras/path_id /sbin
cp extras/eventrecorder.sh /lib/udev
rm -rf /etc/udev/rules.d/*

Third you will need the udev package that the Cross-LFS team developed.
I keep tarballs available on my system for download

http://ftp.jg555.com/udev/udev-cross-lfs.tar.bz2

To install this package use make install

Then make sure you remove your hotplug script if you have it running in /etc/rc.d/