I got this from hohle, but the formatting on Jon’s post is less-than-ideal. So here it is, reposted for easy copy/paste:
Download his applescript here.
And here’s the plist:
Just make sure to change your plist to point to wherever you keep AuthSync.scpt. Then save it to
~/Library/LaunchAgents/local.isync.sync.plist and run the following from your Terminal: