I think I've fixed the problem with my DynDns name expiring. I enabled telnet on my WRT54G and then telneted in and used "vi" to create /etc/cron.d/dyndns containing:
3 4 5 * * root /usr/sbin/ez-ipupdate --service-type=dyndns --user=username:password --host=hostname.homedns.org --interface=eth1
This should mean that the DynDns name will be updated at 04:03 on the 5th of each month.
I decided to update only once per month as the DynDns terms and conditions state only every 28-35 days. We'll see if it works...
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