Cisco ASA 5505

I have just purchased an ASA 5505 and see that my DMZ is listed as restricted. Best I can tell is that this mean I have to make a choice of either allowing communications between my outside with the DMX or my inside with the DMZ, but not both. So this poses a problem when it comes to my mail server correct? If i want my inside network to connect to the mail server I will not be able to allow outside access to the mail server. Is this correct? What work arounds might be avaiable?

Thanks In Advance