how to use iphone 5 with exchang 2003?

Hi all

I have just bought a iphone 5.

Our company is using exchange 2003

I am not able to receive mails at all, and are only able to send one mail at a time if I Iturn on and of the "use SSL" function.

I have tryed to turn "push" on and of, but no sucsess.

Rgds

Audiofil