OS X :: Email Accounts With Different Names But Same Host Confusion

Im very green to the apple way of computing, before I got this new aluminum macbook from santa I've always used windows. Anyway, I am loving my new apple but of course transferring all my old stuff and getting used to how the new programs work can be quite a hassle. Right now im trying to get apple mail to function like outlook did. Please be patient with me. I have several email addresses, private, business, hobby, etc. They go with several of my websites. But they are all hosted with the same server, so although every email has a different name, they all use the same mail server, user name and password.

I know I can add new accounts and by adding different email addresses to the name, divided with a , I can send emails from different addresses. But here is my problem. Every email I send comes from the same sender, the same name but a different email address. info@hab.nl & jo@jo.nl all come from sender Jo, not from hab & jo as I would like. Everytime I try to add a new account I get this message; "The account "jo" already has this hostname and username". I know it does! But I still want to use those with different email accounts, just like I used to do in Outlook.