2 issues of using reCAPTCHA

I recently intergrade reCaptcha into my web and found 2 issues First : (Client side) When user first time check "I am not a robot", everything is working fine, but if the user stay in this page for a while and the reCaptcha turns to timeout, then the user check "I am not a robot" again, it pop-up an error says "invalid reload parameters" Second : (Server side) When first time get response from server side, everything is working too, but if I get second time(before reCaptcha timeout) by the same reCaptchaResponse, it returns fail without error codes. I am using .NET WebClient.DownloadString to verify through the URL http://bit.ly/1EfxUFZ} Anyone meet the same issues and got solutions? Thanks -- You received this message because you are subscribed to the Google Groups "reCAPTCHA" group. To unsubscribe from this group and stop receiving emails from it, send an email to recaptcha+unsubscribe@googlegroups.com. To post to this group, send email to recaptcha@googlegroups.com. Visit this group at http://bit.ly/1dkFnYd. For more options, visit http://bit.ly/P65DvS.