I noticed that when syncing, the animated syncing icon is sometime replaced with a some kind of "light bulb" or "sun" icon (can't be more precise sorry)

At first I just thought it indicates syncing is finished, but it did not appear everytime...

Then in some of my accounts, I found out a "Error Reports" folder. And noticed the light appeared every time an error was added to it.

First question : is this really an error indicator? Why is it not more explicit?

Second question : why does my gmail account show this indicator, but does not have a Error Report folder? Why can't I see the errors in that account?

Here is the version I use
Product name: * *Zimbra Desktop
Product version: 2.0.1
Build ID: * * * *10659
Release type: * *GA
OS Platform: * * Mac OS X i386 10.5.8