How to resolve 'RootViewController' may not respond to '-parseXMLFileAtURL:' in Xcode 3.2.3

Question

I'm making a simple RSS feed iPhone app, and I run into this:

- (void)viewDidAppear:(BOOL)animated {
 [super viewDidAppear:animated];

 if ([stories count] == 0) {
  NSString * path = @"myfeedURL.rss";
  [self parseXMLFileAtURL:path]; <-------Error Here
 }