1) Download the stunnel installer exe from this site (its free)
2) Within the c:\program files\stunnel\stunnel.conf file, comment out the default gmail settings by placing ; in front of every line
3) Copy and paste this to the bottom of the config file below ; vim:ft=dosini
client = yes
debug = debug
accept = 127.0.0.1:1100
connect = pop3.xtra.co.nz:995
accept = 127.0.0.1:259
connect = smtp.isp.com:465
4) Save the config file and start the stunnel program - easiest way it to start the GUI from the windows start menu
5) Set your pop3 connector to download mail from the server 127.0.0.1 and port 1100
6) Go to telecom's website and apply for port 25 unblocking - took two hours yesterday afternoon.
7) Reboot your router
You should be able to use the following command at the command prompt
telnet smtp.vodafone.co.nz 25
If you hit enter and get a blank screen, or welcome message, then the port 25 is indeed now unblocked.
8) Open the exchange SMTP connector properties and set it from "forward all mail through a smart host" to
"Use DNS to route to each address space on this connector"
This means the exchange server will stop relaying through smtp.xtra.co.nz. Instead for each outgoing message it will go and find the MX server of the recipient (eg vodafones email server for @vodafone recipients) and deliver to the vodafone server directly.