title: cocos2d: Subclassing CCMenuItem triggers a lot of "removeChildByTag: child not found!"
body: <p>I am trying to subclass a CCMenuItem using the following code:</p>
  
  <p>GenericButton.h</p>
  
  <pre><code>#import &lt;Foundation/Foundation.h&gt;
  #import "cocos2d.h"
  
  @interface GenericButton : CCMenuItemSprite {
  
  }
  +(id) itemwithTitle:(NSString*)title withBGColor: (ccColor3B) bgColor andFGColor:(ccColor3B)fgColor;
  @end
  </code></pre>
  
  <p>GenericButton.m</p>
  
  <pre><code>#import "GenericButton.h"
  #import "HelpfulClasses.h"
  
  @implementation GenericButton
  
  +(id) itemwithTitle:(NSString*)title withBGColor: (ccColor3B) bgColor andFGColor:(ccColor3B)fgColor{
  
  CCSprite*genericButtonBG = [CCSprite spriteWithSpriteFrameName:@"genericButtonBG.png"];
  genericButtonBG.color=bgColor;
  
  CCSprite*genericButtonBGPressed = [CCSprite spriteWithSpriteFrameName:@"genericButtonBGPressed.png"];
  genericButtonBGPressed.color=bgColor;
  
  CCMenuItemSprite*button = [CCMenuItemSprite itemWithNormalSprite:genericButtonBG selectedSprite:genericButtonBGPressed];
  
  CCSprite*fgButton = [CCSprite spriteWithSpriteFrameName:@"genericButton.png"];
  fgButton.color=fgColor;
  [button addNodeInMiddleOfParent:fgButton];
  
  CCLabelBMFont *buttonTitle = [CCLabelBMFont labelWithString:title fntFile:@"font.fnt"];
  if ([title length]&gt;7) {
  buttonTitle.scale=0.85;
  }
  buttonTitle.color=ccYELLOW;
  [fgButton addNodeInMiddleOfParent:buttonTitle];
  
  return button;
  
  }
  // on "dealloc" you need to release all your retained objects
  - (void) dealloc
  {
  // in case you have something to dealloc, do it in this method
  // in this particular example nothing needs to be released.
  // cocos2d will automatically release all the children (Label)
  
  // don't forget to call "super dealloc"
  [super dealloc];
  }
  
  @end
  </code></pre>
  
  <p>But whenever I am using GenericButton*button = [GenericButton item....], in a CCScene, there is a lot of"removeChildByTag: child not found!" showing on the console. Am I doing something wrong?
  Cheers</p>