title: What format is java's cacerts format expected to be?
body: <p>I'm slightly confused about cacerts formats.  An application I use recently had to upgrade it's cacerts file. The original cacerts file was pk12 format (I assume, it's binary), while the new format is clearly pem.  I can use either cacert, but when I suggested someone having trouble with authentication upgrade to the new cacert he gets complaints because it is not a pk12 format.</p>
  
  <p>What file format should cacert's be?  can it be either format?  Does something configure/define which format it should expect?</p>