MyGUI pointer lag

Today I enable MyGUI pointer and system pointer at same time in my game.
And I noticed a slight lag of MyGUI pointer from the system pointer during quick mouse movement.
In the game, it feels like a bit sluggish cursor. Can I do something to get rid of this lag?

Or the way it should be?

I guess you are updating UI after frame rendered, so your cursor is one frame below real one.
Or may be you have some other delayed cursor handling.

I call mInputManager->injectMouseMove() in my GameManager::mouseMoved(). Can I do it else?