I have implemented a "site feedback" form that uses a captcha and noticed the captcha image was not reloading to reflect the correct values so the user input would always fail after the first form was submitted. I tried dissabling caching on the page level from the CMS Desk, but this did not help. I have now added:
Response.Cache.SetCacheability(HttpCacheability.NoCache);
to the Page_Load event of CaptchaImage.aspx in CMSPages and it is working great.

Please included this code in your next release so I do not have to remember why my forms break upon upgrade.

I love the product and thanks,
Jason