Mail proxy and WAP on a sonicwall DMZ

I have a sonicwall TZ170. I currently have nothing on the OPT port. I would like to put a mail proxy (spamfilter) to gather incoming mail and forward it into my mail server on my LAN. I would also like to put a wireless access point out on the DMZ'd OPT port, so I can have a laptop connect to the WAP, and then use a VPN tunnel into a 2003 Windows Server. I am completely unaware on how to do this. My internal network is 192.168.1.1-192.168.1.255. Would I make the DMZ network