cwm flashes just fine and works, /system/etc/install-recovery.sh resinstalls stock recovery on every boot.
when you flash with odin uncheck auto-reboot, when it passed power y ou pull the battery, then put it back in and press and hold the buttons to get into recovery. if you boot into android at all once you flash cwm you will lose it.
once youve booted into recovery at least once it will remove the script for ya when you try to reboot
tada, i just rooted your jellybean update as well now, do i win a prize?