Hi ghostlywind, I'm looking into this also -
dnsmasq man page: http://thekelleys.org.uk/dnsmasq/docs/dnsmasq-man.html
Given the error you're getting, it looks like it's trying to write the lease file to a non-existing path location.
Check your /etc/dnsmasq.conf
There should be an entry in it like this:
dhcp-leasefile=/tmp/dhcp.leases
I just checked the processes running on my newly built (stock) Jasager, and found the following:
/usr/sbin/dnsmasq --dhcp-range=lan, 192.168.1.100,192.168.1.250,255.255.255.0,12h
You could try that...
vendox