Hostname, Exim and Nameserver issue

I think I have created a problem and need some insight. :D

When I set up my server, the main server name (server.mydomain.com) has an ip of:
x.x.x.242

I configured 2 nameserver domains, ns1 and ns2:
ns1: x.x.x.242
ns2: x.x.x.243

I've been getting complaints that email sent from the server is going to Yahoo's bulk/junk folder. It turns out that it is being sent from server.mydomain.com but the RDNS points to ns1.mydomain.com.

So, my guess is that I shouldn't have assigned the ns1 ip to be the same as server.mydomain.com.

What should I do? I thought about changing the hostname, but in the docs it says:
"This means that your hostname should never be a domain name and especially not the name of your domain!!". So I'm guessing that changing it to ns1 is a bad idea.

So, then I'm guessing I need to change ns1 to a different IP. My concern is that I have 20+ domains on this server and if I change the IP, I'm not sure if that requires a change for each of the domain registrars?

Thoughts/suggestions?

Thanks!

 

Thanks johnmigen!

For some reason, I thought that would cause problems, but I guess there is no need for a nameserver to reverse lookup an IP.

I appreciate it!

 

Well, I haven't done it yet and will need to wait to see if it causes any nameserver issues, but if all goes will, I'll let them know.