title: UILineBreakMode Vs NSLineBreakMode
body: <p>I see some UIStringDrawing methods have been updated to use NSLineBreakMode instead of UILineBreakMode in iOS 6.0:</p>
  
  <p>E.g.</p>
  
  <pre><code>- (CGSize)sizeWithFont:(UIFont *)font constrainedToSize:(CGSize)size lineBreakMode:(NSLineBreakMode)lineBreakMode
  </code></pre>
  
  <p>How can I check for this to ensure my iOS 5 users and below continue to use UILineBreakMode?</p>