I'm compiling the BlueZ packages on Slackware64-13.0 and bluez.Slackbuild failed to run. I added
mkdir -p $PKG/lib/udev
cp -a scripts/bluetooth_serial $PKG/lib/udev/bluetooth_serial || exit 1
and now the script runs.
I don't know why the /lib/udev directory isn't created earlier in the build process for me, but now it builds cleanly. Anyone else run in to this?