Leaks, any tips?

I'm new to testing for leaks with the mac instrumentation.

I get this with my initial test app... if I understand correctly it's saying in the EAGLView.mm the call to "presentRenderbuffer" is doing a calloc which isn't tracked... is this something expected? Or is something not setup with renderbuffer properly?

8 UIKit -[UIView(CALayerDelegate) _layoutSublayersOfLayer:]
7 myApp -[EAGLView layoutSubviews] /iPhone/myApp/Classes/EAGLView.mm:114
6 myApp -[EAGLView drawView] /iPhone/myApp/Classes/EAGLView.mm:98
5 OpenGLES -[EAGLContext presentRenderbuffer:]
4 OpenGLES GLESFlushBuffersGC
3 OpenGLES FlushHW
2 OpenGLES PrepareToDraw
1 OpenGLES FramebufferMakeResident
0 libSystem.B.dylib calloc

- (void)drawView {
if( sio2->_SIO2window->_SIO2windowrender )
{
sio2->_SIO2window->_SIO2windowrender();
sio2WindowSwapBuffers( sio2->_SIO2window );
}
glBindRenderbufferOES(GL_RENDERBUFFER_OES, viewRenderbuffer);
[context presentRenderbuffer:GL_RENDERBUFFER_OES];
}