[Exim] IP address in host_list?

I need to include either a list of ip addresses or of network items in
a "host_list" item (exim 3.0x). How do I do that? ( I will note the
network items will just be /32's)..


I currently have the following

host_accept_relay = " lsearch;/etc/exim/pop_smtp_auth : ! *"

and have a format of

10.0.0.1/32:foo
10.0.5.6/32:bar

in that file.....