In-Bound Mail Problem

[byreferralonly]

I originally setup by sugar install and it had no problems. Now my inbound mail has stopped working. I am on a shared server.

FreeBSD red.eboundhost.com 6.2-RELEASE-p9 FreeBSD 6.2-RELEASE-p9 #0: Wed Dec 12 00:22:43 CST 2007 supporter1@red.eboundhost.com:/usr/obj/usr/src/sys/MYKERNEL i386

PHP Version 5.2.6

Sugar CE Version 5.0.0e (Build 3276) (I have other Sugar version running for different clients all on the same shared server and running the same PHP)

I even did a new install with Sugar CE Version 5.0.0f

They ALL have the same issue. When I try to setup a new email account it give me the error.
Test Settings
No such host as mail.domainname.com
Please check your settings and try again.

I tried pop3/imap and gmail no inbound will work.

For account that were working when I go in to edit them and use the test button. I get the same error also.

I have read all the posts I can find on this issue and have tried the different suggestion but nothing fixes it. Also on the new installation there are not any errors logged for this issue.

I did notice that on the one account when I upgraded from 5.0.0d to 5.0.0e on May 16 I no longer received and email on that account but I did on other,

Any help would be appreciated. I have run a full diagnostic as of today. I have attached the diags.zip file. This is for a non production installation that I did yesterday to try and isolate the issue. The logs are as clean as they are going to be. And everything else is up to date. As I said I have this in 4.5.1h to 5.0.0f so it is a server issue some place.

The only installation that continues to work fine for me is on my laptop. I have ver 4.5.1j running Windows Vista Home Edition. PHP 4.4.3

[byreferralonly]

My hosting company was able to help me resolve this issue. Instead of using:

mail.domainname.com which was my mail server. They had me use the IP address xxx.xx.xxx.xx That solved the problem for me. If anyone else has a similar issue try that solution. I had the issue across several domains that were on the shared server. I implemented it for each Sugar installation and they all work fine now.