title: how to define two foreign keys in cakePHP
body: <p>I got a table with a few columns.<br/>
  The table has a primary key (replyid), and two foreigne keys (userid and postid).</p>
  
  <p>Here is the structure of the table:
  {replyid, content, userid, postid}</p>
  
  <p>The Reply table got two foreigne keys. <br/>
  I am not sure if this is a correct to set the foreign keys like this:<br/></p>
  
  <pre><code>class Post extends AppModel{   
      var $name = 'Post';
      var $useTable = 'post';
      var $primaryKey = 'postid';
      var $belongsTo = 'User';
      var $hasMany = array(
          'Reply' =&gt; array(
              'className'     =&gt; 'Reply',
              'foreignKey'    =&gt; 'postid',          
              'foreignKey'    =&gt; 'userid'     
                          )
                          );  
  
                              }
  
  ?&gt;
  </code></pre>
  
  <p>Could you helpplease?</p>