aakk9999 - 1:50 am on Jul 1, 2012 (gmt 0)
I have seen CMS site pages get cached right after creation but the author was creating the page for a story that wasn't finished, the CMS doesn't actually have a rewrite assigned to the content and somehow crawlers see it, try to hit the page and get a 404.
This is not quite what is happening. If the page returned 404, Google would never cache its content as 404 means "Not found".
What has most likely happened is that the CMS returned the content of its 404 message, but the HTTP response was 200 OK. In which case, Google cached the page content as it was told that the page exists. There are milions of such cases all over the web and the reason for this is the CMS not handling 404 response properly and is not Google's fault.