[Exim] receiver_verify_*

A week or so ago, to avoid excessive mail rejection notices getting stuck in
my queue, I added three lines to my exim.conf files:

receiver_verify = true
receiver_verify_hosts = *
receiver_verify_addresses = *

This has completely succeed at what I wanted do, but it has had a side
effect. This server acts not to accept mail for several domains (public
incoming requests), but also queues outgoing mail for delivery from a
handful of hosts. With the above three settings in place, I encounter
timeouts when attempting to queue (send) email from my Windows client, a
LOT. Most mail messages seem to encounter at least one timeout.

Now, logically, what I want to do is restrict when receiver_verify is used,
and that's what the later two settings are for, according to my
understanding. But what I want to do is say "verify the receiver for all
incoming mail messages, except those that are from a host/address in this
list. I took a look through the documenation, and I'm not sure if this is
possible. It looks like it might be possible using regular expressions, but
I thought I should ask for help.

I think that adding:

receiver_verify_addresses=^!((192.168.100.\d{1,3})|(x.y.z.(49|50|51|52|53|54
|56|57|58|59|60|61|62|63)))

will match all machines that are not on one of the two following networks:
192.168.100.0/24 and x.y.z.48/28

Does that look right to you? Is there a better way to do this?

Thanks. David Corbin