Heh, sorry, I didn't actually try the second link, I just saw it and thought I would mention it. Oops.
Anyway, Avast is probably set up to try to keep anyone from unintentionally downloading, and possibly automatically running, an executable. Tricking people into running programs is the #1 way of getting into their machines.
If you tell it that you trust xim3.com and xim4.com, it will probably not interfere anymore.