Why OpenEMM is so limited in mail settings???

[titobustillo]

I am trying to change from SugarCRM Campaign module to OpenEMM because I think OpenEMM is easy to work with it . But the great problem I have found is its limited mail settings capability.
With SugarCRM, Its so easy to configure an external SMTP server, its port, etc, so with it there is no problems with reverse and mails never are marked as spam.
But, with OpenEMM I cant configure in the same way. If I use sendmail, mails are sended without problem, but I have been blacklisted.
Any solutions to it??
Thanks.