Bad scripting causes LDM to fail to start in the client, on karmic

Binary package hint: ldm

I'm running up-to-date Karmic; the generated LTSP client fails to run.

Specifically, On VT7 you get continual spamming of the message 'mktemp: Too few X's in template /var/run/ldm-xauth-<random>/Xauthority'. The ldmgtkgreeter is restarted in an infinite loop, which is seen in /var/log/ldm.log

The problem is line 53 in the client image's /usr/share/ltsp/screen.d/ldm script:
    51 XAUTHORITY_DIR=`mktemp -d /var/run/ldm-xauth-XXXXXXXXX`
    52 export XAUTHORITY_DIR
    53 XAUTHORITY=`mktemp -u ${XAUTHORITY_DIR}/Xauthority`
    54 export XAUTHORITY

mktemp expects a string of the format in line 51. Without the multi-char X string, it fails with the error message already mentioned.

Solution is to replace the 'mktemp' with a 'touch' command, setting the XAUTHORITY value appropriately. On my machine, this gets me X started - although the machine then freezes! (laptop, nvidia driver, etc, etc).