Hmmm,

I think that we now have multiformat bots from what I have been seeing. Shouldn't be that difficult I would have thought..........some sort of initial probe would then activate the appropriate subroutine?

The captcha thing is interesting as I suspect that the botmasters must have copies of the normally available fonts. It would be intersting to see what effect a custom captacha font had?............... I know, I know "security through obscurity"