problems with zmailer and dns

["E.Colanski" <ecol@ibud.vr9.com>]

Hello!
I have zmailer ver 2.99.52-patch1 based on solaris7/x86.
When I try to set up in smtp-policy.src:
.                      relaycustomer - relaytarget - senderokwithdns +
[0.0.0.0]/0            relaycustomer - relaytarget - senderokwithdns +

my mail queue is filling up very quickly with even 800 msgs staying
there. And messages go out from there very slowly (it takes hours...)
But when I set up:
.                      relaycustomer - relaytarget -
[0.0.0.0]/0            relaycustomer - relaytarget -

it works quite efficiently.
While msgs were staying in the queue I checked some sender domains:
host -t mx sender_domain_from_any_mail_from_queue

and proper answer appeared.

What can cause such big delays in working of router?

Also I noticed that there are some messages in
/var/spool/postoffice/public even older than 2 days. Why haven't they
been processed so far?

I have set up auxiliary named-8.2.2-P5 on mail gateway for speedeing up
name resolving but without effects.

And 3rd question even if I set in /opt/mail/smtpserver.conf maximum
message size to 2MB larger maessages are welcomed on my machine and they
are kept in error state on my disk for few days. How to forbid taking
oversized msgs by zmailer?

Could anybody tell me any advice how to solve it? It's really important
for me.

Regards

E.Colanski