One of our machines was recently put behind an SSL proxy and since then I can't connect to puppet with "Could not evaluate: certificate verify failed."
I have checked that the dates match, regenerated the certificates but to no avail.
Debugging the verification with "openssl s_client -showcerts -connect puppetmaster:puppetmasterport" shows "Verify return code: 0 (ok)"
Initially the Proxy SSL Certificate was not recognized with a "Verify return code: 20 (unable to get local issuer certificate)" problem which was then fixed with the answer in the question: Adding root certificate to CentOS 5
This seems to have solved my problem:
Reference: https://groups.google.com/forum/?fromgroups=#!topic/puppet-users/VVGkYArpYfI