I have an 2003 exchange server that Is configured with ISA 2006. I have a certificate configured with the name msr.domainname.com that points to it. The only outside services we are using are activesync and outlook over RPC. I want to set this up to point to our exchange 2007 CAS server so I can move these people over to the 2007 Exchange server. Right now the exchange 2007 server is using the self signed cert for internal stuff. I am really confused as the what I need to do certificate with for the new certificate for exchange 2007. I need to setup a new IPhone for someone that is on the Exchange 2007 server so even if I had to used the self signed cert temporally I am open to that.