vards/avatars aren't refreshed when "show av. in roster" is checked
when you install gajim and have a new configuration and no avatars downloaded yet, and start gajim, no avatars are shown. when you uncheck and check "show avatars" in the prefs, the vcards aren't refreshed, and thus the avatars aren't either.
i had to open the information dialog for every contact myself, so the vcard and the avatar would get updated and then finally the avatars were shown.
i could reproduce this with 0.11-2 on windows and svn on linux.