Centos ipsec server for iphone clients with NAT

I require a virgin centos server be configured with openswan ipsec server so that multiple iphone ipsec clients can attach. ill provide root access to the box but i need logs so that i can re-create configs on a live box myself. The box has 2 interfaces (public and private) the private can be ignored as all vpn traffic will terminate on the public one. All VPN connections, will need to NAT traffic back out of the public interface. This is to simply allow all iphones to behave like they have a single ip address (the servers public ip). please only bid if you have done this before. I also require a "how to" document so i can replicate this config onto existing centos 5.5 servers. just a list of commands and basic instrutions will suffice as long as i can reproduce it. for those who do not know, the iphone does not have client certificates and uses a cisco VPN setup on ipsec.