title: Issue in UITextView beginningOfDocument in iOS 4.3
body: <p>Below is the code which I am using and working fine in simulator iOS 5+, but giving issue in simulator 4.3</p>
  
  <pre><code>UITextPosition *begin = [self.tvQuestion positionFromPosition:self.tvQuestion.beginningOfDocument offset:nrange.location];
  </code></pre>
  
  <p>Following is the error statement:</p>
  
  <blockquote>
    <p>Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UITextView beginningOfDocument]: unrecognized selector sent to instance 0x5586050'</p>
  </blockquote>
  
  <p>Could somebody advice on this? Thanks in advance!</p>