title: Cryptographic Exception Invalid flags Specified
body: <p>Here is my code:</p>
  
  <pre><code>        RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(128);
  
          try
          {              
              string publicKeyXML = rsa.ToXmlString(false);
              string privateKeyXML = rsa.ToXmlString(true);
              int size = rsa.KeySize;
          }
          finally 
          {
              rsa.PersistKeyInCsp = false;
          }
  </code></pre>
  
  <p>I just keep getting the same error "Invalid flags specified". If I use the no-argument constructor, no exception is thrown and the keysize is 1024.</p>