How to configure DNS If I use the plugin yet-another-multi-site-manager?

I just configured yet-another-multi-site-manager and I can able to use internal sub-domains like 1.domain.com and 2.domain.com as alternate domains .I can able to create sub-sites on those domains successfully like try.1.domain.com .

But Unfortunately when I set external domain(Primary domain Registered some where else) the sub-site’s URL showing error page..

Example:
3.domain.com is addon domain pointing to my multi-site installation folder .A sub-site created under it is try.3.domain.com .This sub-site’s URL showing error page.

Actually I am pointing that external domain pointing to Numeric IP(My hosting is shared hosting) address of my multisite domain.Later adding that domain as an addon pointing to my Multisite installation folder .

Does any one have Idea on this?I think that I have wrongly configured the DNS of Addon domain .

Update:
Now I am able to create sub-sites using the additional domains .But the problem is when logging into the sub-sites created on these domains .The login pages are again redirecting to login form and the loop continues .I am even unable to edit the sites using the option “Backend” on admin panel .

Update 2:
The code inside the yamm-signup.php page and yet-another-multi-site-manager.php are not updated as per the updated new version 3.1 .The plugin is prepared for wpmu not updated for a long while .

You will have to get a dedicated IP to make things simpler.

It works exactly like the domain mapping plugin, with the exception that you need to create a wildcard A record.

Unlike domain mapping, you can’t get around the dedicated IP requirement by parking the domain, as parking will only cover the main 3.domain.com, and not any non existing *.3.mydomain.com subdomains. cPanel does not seem to support this via their admin interface. It is however possible to manually edit your apache conf file and add them to the ServerAlias line in your virtualhost: ServerAlias 3.domain.com *.3.domain.com