Hi,
OWA uses port 443 and is a web address. The iphone uses either IMAP, POP or Active Sync.
If you want to read your emails on your phone, you can use your phone's browser and point it to your owa address, but that would be only like reading your emails via OWA, and you don't have access to any appointments etc.
Either way, you need to ensure IMAP is enabled and published on your firewall, but more likely if they don't know how anything about active sync, it's unlikely IMAP is published either.
The answer to your question is you can't make Iphond sync mail to an OWA web site. It has to be active sync to active full featured mail client.