[exim] Reverse DNS

In the past I have tried to block/defer users with no reverse DNS in
exim.conf. Tried both the following.

# : no reverse dns
#defer
#       !hosts      = net-lsearch;/etc/virtual/pophosts :
/etc/virtual/relay_ips : 127.0.0.1
#       !verify     = reverse_host_lookup
#               message     = Reverse DNS lookup failed for host
$sender_host_address

#defer
#!condition     = ${lookup dnsdb{defer_never,ptr=$sender_host_address}{yes}}
#!hosts         = net-lsearch;/etc/virtual/pophosts :
/etc/virtual/relay_ips : 127.0.0.1
#       message    = Reverse DNS lookup failed for host $sender_host_address

I want to block users with no reverse DNS except my users trying to
relay or authenticated users. It seems to block all users with no
reverse DNS including those in pophosts. Any idea what I am doing
wrong?

Matt