title: cURL says certificate is expired, Firefox disagrees
body: <p>I'm trying to access an internal site via cURL (which I could access several days ago). However, cURL gives the error <code>curl: (60) SSL certificate problem: certificate has expired</code>. If I use <code>openssl</code> to check the start and end dates of the certificate, it gives a timeframe that I'm well within:</p>
  
  <pre><code>echo | openssl s_client -connect internalsite.example.com:443 2&gt;/dev/null | openssl x509 -noout -dates
  notBefore=Nov 30 00:00:00 2012 GMT
  notAfter=Mar 30 12:00:00 2016 GMT
  # For reference, the day I'm posting this is July 30th, 2014
  </code></pre>
  
  <p>Additionally, if I use cURL on a different computer, or connect via the browser (Firefox, Chrome, or IE), I can connect without error.</p>
  
  <p>Also, I'm unable to connect with any version of cURL on my own computer; this includes cURL in Cygwin and cURL on Ubuntu inside a virtual machine, as well as the Windows version.</p>
  
  <p>What might give rise to this behaviour?</p>