Automatically Sync entourage to google calendar

I have to use Entourage on my machine for various reasons, and I want to sync my Entourage calendar to my Google Calendar. I've got it set up to automatically sync my Entourage calendar to iCal, and that works fine. I've also got iCal set up to sync my Entourage imported calendar to Google, and that works fine. What it doesn't do is automatically publish changes - even though the "Publish changes automatically" box is ticked - I assume because I'm not changing the events myself but they are being imported from elsewhere. Is there a way to get this to work as I want? Or, better yet, is there another way to get Entourage to sync to Google Calendar? (Off topic I know, and I can't find an answer anywhere else so I'm not hopeful)