title: NSString to NSDate issue IOS7
body: <p>I'm using the following code to convert <code>NSString</code> to <code>NSDate</code>:</p>
  
  <pre><code>NSDate *date = [NSDate convertStringToDate:strDate andFormatter:@"MM dd"];
  
  + (NSDate *)convertStringToDate:(NSString *)dateString andFormatter:(NSString *)formatter
  {
      NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
  
      // this is imporant - we set our input date format to match our input string
      // if format doesn't match you'll get nil from your string, so be careful
      [dateFormatter setDateFormat:formatter];
  
      dateFormatter.timeZone = [NSTimeZone systemTimeZone];
  
      return [dateFormatter dateFromString:dateString];
  }
  </code></pre>
  
  <p>NSString is <code>@"07 15"</code>. But my NSDate is <code>nil</code>. On a simulator it is fine but on device with iOS7 it is nil.</p>
  
  <p>Do you have any suggestions about it?</p>