[Exim] router condition

Hi Friends,

I want to run a router only for senders from outside the network. This
is a DSPAM router:

dspam:
  driver = accept
  no_verify
  condition = ${if and {{!def:h_X-Spam-Flag:} \
    {!def:h_X-FILTER-DSPAM:}}{1}{0}}
  headers_add = "X-FILTER-DSPAM: by $primary_hostname on $tod_full"
  transport = dspam_check

1) How would this be done by IP address on a 192.168.193. network?

2) How would this be done by named list search?
    e.g. I tried this in the condition that didn't work
    {!eq{$sender_address_domain}{+local_domains}}

Thanks,
Craig