[web2py] anybody ever try to do modal registration using only web2py and recaptcha?

[weheh]

I'm trying to do modal registration with a custom form, recaptcha, and an 
ajax follow-through after processing. Recaptcha may have sunk this 
approach. Can you suggest a secure alternative that works better with 
jQuery? Or perhaps give your account of how to do modal registration in 
web2py?