Ok anyone got any idea why I can't allocate a depth buffer in the iPhone simulator ? I'm doing:

  CAEAGLLayer *eagl_layer = (CAEAGLLayer *) view.layer;
  eagl_layer.opaque = TRUE;
  eagl_layer.drawableProperties = 
    [NSDictionary dictionaryWithObjectsAndKeys:
    [NSNumber numberWithBool:FALSE], kEAGLDrawablePropertyRetainedBacking,
    kEAGLColorFormatRGBA8,           kEAGLDrawablePropertyColorFormat,
    nil];
  ogl_ctx = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES1];

  ...

  [EAGLContext setCurrentContext: ogl_ctx];

  double s = self.contentScaleFactor;
  int w = s * [self frame].size.width;
  int h = s * [self frame].size.height;

  glGenFramebuffersOES  (1, &gl_framebuffer);
  glBindFramebufferOES  (GL_FRAMEBUFFER_OES,  gl_framebuffer);

  glGenRenderbuffersOES (1, &gl_renderbuffer);
  glBindRenderbufferOES (GL_RENDERBUFFER_OES, gl_renderbuffer);
  glRenderbufferStorageOES (GL_RENDERBUFFER_OES, GL_RGBA8_OES, w, h);
  glFramebufferRenderbufferOES (GL_FRAMEBUFFER_OES,  GL_COLOR_ATTACHMENT0_OES,
                                GL_RENDERBUFFER_OES, gl_renderbuffer);

#if 1 // #### why you no worky
  glGenRenderbuffersOES (1, &gl_depthbuffer);
  glBindRenderbufferOES (GL_RENDERBUFFER_OES, gl_depthbuffer);
  glRenderbufferStorageOES (GL_RENDERBUFFER_OES, GL_DEPTH_COMPONENT16_OES,
                            w, h);
  glFramebufferRenderbufferOES (GL_FRAMEBUFFER_OES,  GL_DEPTH_ATTACHMENT_OES, 
                                GL_RENDERBUFFER_OES, gl_depthbuffer);
#endif

  [ogl_ctx renderbufferStorage:GL_RENDERBUFFER_OES
           fromDrawable:(CAEAGLLayer*)self.layer];

  switch (glCheckFramebufferStatusOES (GL_FRAMEBUFFER_OES)) {
    ...

I'm getting GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT_OES. If I don't allocate the depth buffer, I get no error, but of course neither does depth testing work.