title: Android NFC Mifare Classic authentication issue
body: <p>I wrote some code for authenticating to and reading from Mifare Classic cards on Android. It works perfectly on the first generation of Nexus 7 (2012) as well as on Samsung Galaxy Nexus I9250. However, it fails on a Samsung S3 Mini. The devices detects the card correctly as MifareClassic and I can use the <code>connect()</code> method of the <code>MifareClassic</code> object to connect to the tag, but it can't authenticate using either of the two available methods <code>authenticateSectorWithKeyA</code> or <code>authenticateSectorWithKeyB</code>. However, with the same code, authenticating and reading the data works correctly if using any of the other devices mentioned above!</p>
  
  <p>My questions are:  </p>
  
  <ol>
  <li>Is the authentication/encryption of the communication a hardware operation? Or is that done in software?</li>
  <li>Why can the device connect to the tag but not authenticate to it?</li>
  </ol>