Wow brother hang on there. You see, captcha is made against those who are using scripts to flood their database. if there is a way doing this, it would be soo advance and might probably not use PHP for this. Please listen to my advice, if you're up to something, please reconsider your acts. You know there is some legal actions for this :)
I concur. Or unless you are willing to prove to the whole community that captcha can be bypassed. Like what some researchers from some University have done that(sorry I forgot) but that was a long time ago and their captcha breaker program is not working anymore.
So if I were you, listen to Master ardav, just be creative. not be destructive