I read elsewhere and tried it - clear the cache for Gmail. I went ahead and cleared anything related to Google as well as my calendar. I restarted it and resynced it all and now it works fine.
Try it out. So far, so good. Now, even my optical trackball works again (before, it used to work for a few minutes and then suddenly stop working - it was definitely related to that error because once, it happened right after the error appeared).
Good luck,
Tim