I’ve had quite a few people asking about that kind of setup. I personally did not encounter any issues there, but since more and more people tell me that they cannot connect by using OL2007, when OL2003 works perfectly, makes me wonder if there are any specific client-side settings that are different.
I have it running on my home Exchange 2003 server with two machines connecting without any problems. No ISA server involved.
I did have to configure it the same way as Outlook 2003, so when setting the host I had to put in msstd:host.domain.com – the way the box is worded it looks like you can get away with just home.domain.com.
Haven’t tried it with Exchange 2007 yet as my SSL certificate doesn’t work… grrrr