Hi Brad,
Thanks for your comments. I hear what you are saying about VMware and performance, however, I work in New Zealand and most of our customers have less than 50 users on their Exchange Servers. We've been running 3 Exchange 2007 Servers on our VMware ESX servers (for various hosted customers) with no issues in terms of performance for the last 8 months. Admitedly the VMs do require a lot of RAM (4GB minimum) but otherwise it runs like a dream.
As for the rest of what you say. There's going to be no way I can get round this. Our parent organisation runs Exchange 2007 as well and they already have the DNS records for autodiscover configured for themselves. I've told my boss our employees are just going to have to get used to clicking on the certificate button when it comes up. It only happens when they are outside the network anyway so not a major issue.
Thanks for your response.
Regards,
Richard