DNS Mail Problem

In order to have my mail servers work correctly, I have to enable "Master DNS" under my domain management. I do not, the mail is returned to sender. I dont have a problem enabling the server as the primary dns however I have using port redirection big time with zoneedit's external dns for the world wide web to access my website. Without Master DNS enabled when i access my website from a lan computer it works fine following the zoneedit's rules but now when I try to access my website with MASTER DNS enabled, it will take there however none of the links work becuase they all need the redirection to a different port. Is there some way to keep Master DNS enabled just for the mail server and somehow still use the dns from zoneedit even when accessing from lan?

Thanks
Joe