I had similar issues, and found a solution that worked for me.
1. First of all, you will need a server (Linux, Windows or Mac), that your mobile device can access (most likely accessible from the Internet).
2. Download DavMail from SourceForge on your server. Configure it (very easy), and start it. Expose the server ports to the Internet if needed (use SSL for sharing on the Internet).
3. DavMail can now act as a "gateway" between your mobile device and the Exchange server. For the calendar, it "translates" the Exchange calendars to CalDav
4. Add the CalDav calendars to your mobile device. I'm using CalDAV-Sync Beta for my Android phone, but you might find another application.
Not the easiest solution, but not that hard actually, just follow the HowTo on DavMail site.
Hope this helps.