I'm having the same problem. Specifically free/busy time is not available and the outlook debug log shows this is because autodiscover is failing.
I'm using CrossOver Version 7.1 (7.1.0) on Mac OS X (10.5.5) Using the winxp bottle. I registered for the free download of crossover on the special give-a-way-day.
Our autodiscover service works fine when I use outlook via a V.M. or boot into real Windows, but using a packet sniffer on my machine I found that no outbound connections were being attempted to the autodiscover host when using crossover. Literally no traffic. I'm not even seeing any DNS lookups for the autodiscover hostname.
I have IE 6 installed in the same and am able to surf the web and outlook works fine for checking my mail when I hard-code the exchange server name. I see the IE 6 traffic perfectly fine in the packet sniffer. I also see the traffic when outlook checks my email.
So to trouble shoot the problem further I found that you can setup the autodiscover service to use a local XML file rather then going off onto the network. see "Deploying an XML file" at (http://exchange-genie.blogspot.com/2007/07/autodiscover-ad-attribute.html)
I used my real windows host to grab the autodiscover XML file and then copied it into the drive_c area for crossover.
Using this configuration autodiscover works fine now with crossover. But now that I'm past the autodiscover problem outlook is complaining about not being able to complete the SOAP request for the user availability (when trying to view someones free/busy schedule in the calendar):
Request action: http://schemas.microsoft.com/exchange/services/2006/messages/GetUserAvailability)
Specifically it displays "Response error code: 80070032" and says that there was an error in the request/response.
Again, using a packet sniffer I don't see any attempt to contact my exchange server via the ASURL listed in my local autodiscover.xml file.
So I'm becoming convinced that the problem is not with the autodiscover "feature" or the SOAP service calls as much as it's a problem with the network connectivity or the way outbound requests are being made from Outlook through crossover.
I would love to do some other tests for anyone who is interested. I could/would also be willing to post the full output of the packet trace and outlook debug logs if anyone would like.
--Mark