the neighbour table overflow is caused by the loopback interface not being enabled. I think you will need the command ifconfig to set it :
ifconfig lo 127.0.0.1
maybe it can be done by catting an entry in /proc somewhere?

I must warn you; if it outputs too many stuff to the serial port when there is no receiver on the other end, it can slow down the IR-response

You can also check if you are in the car with a line in your shell-script. Can't remeber right know. Search the BBS for custom init-scripts and you will find various answers...

Frank van Gestel