in reply to
WWW::Mechanize cannot create new gmail account
Short answer as to why this is failing: because Google really don't want you to do this, because they're smart, and because you're not the first person to try.
If you want just one hint on doing things with WWW::Mechanize that websites really don't want you to do? Start by changing the User-Agent string so they don't know you're using WWW::Mechanize.
Nobody says perl looks like line-noise any more
kids today don't know what line-noise IS ...