CAPTCHA going nut

for 4 times captcha apparently block my replies...because result were no correct.

So i had to login to post a reply...but then i had a surprise even if apparently refused all my replies were accepted only with a weird delay

then here http://registry.gimp.org/node/228#comment-4453 the identical replies are not from some spammer trying to publicize the Web Archive side, but result of CAPTCHA hiccups...

Just to let you know.

..is confusing that at first captcha does not accept 2 as result of 2 + 0 , but then after few minutes change his mind and the refused message is displayed