I am seeing this issue on multiple servers running Windows Server 2008 and 2008 R2. When a Mac user running OS X of any version 10.5 or higher (up to 10.7), when they log in to remote desktop and open Outlook, Outlook shows up in the wrong time zone. You can go in to Outlook Calendar Options, change the time zone there, and then the time zone will appear correctly until the user logs off and back on. Then the problem returns. Users running Windows do not experience this issue.
Last time I researched this was a couple of years ago and it was basically "known issue, we're working on it" from Microsoft. I assume this has been resolved, or at least a workaround developed, but I could not find any new info.