i have version 121003-1, and my avast says it's updated version (not outdated anymore). i tried to manual update ( i was curious), and i got this ( see the attachment). and no 'invalid file signature' anymore
well, i think version 121003-2 was a bad update, so they pulled it back. (but the funny thing is, i never had version -2, but my avast said my previous version was 121003-2).