[CCBReader] Memory Leak about CCBReader

hi every body.

i have a question about ccbreader.

i write that code :
cocos2d::extension::CCNodeLoaderLibrary **pNodeLoaderLibrary = cocos2d::extension::CCNodeLoaderLibrary::sharedCCNodeLoaderLibrary;
cocos2d::extension::CCBReader * ccbReader = new cocos2d::extension::CCBReader;
cocos2d::CCNode node = ccbReader~~>readNodeGraphFromFile, this);
ccbReader~~>autorelease;
and i trace node ref Count is 1. autoRelease count is 1.
it’s generate memory leak.
but i try to change like as:
cocos2d::extension::CCNodeLoaderLibrary
pNodeLoaderLibrary = cocos2d::extension::CCNodeLoaderLibrary::sharedCCNodeLoaderLibrary;
cocos2d::extension::CCBReader
ccbReader = new cocos2d::extension::CCBReader(_pNodeLoaderLibrary, NULL, NULL, this);
cocos2d::CCNode *node = ccbReader~~>readNodeGraphFromFile, this);
ccbReader~~>autorelease();
this~~>addChild;
this~~>removeChild(node);

not memory leak.
What causes for this result

i hope any one can help me.

thank.

did you solve this problem?
BTW,which version of your cocosbuilder is ?