render animation not the same as single frames


I have trouble rendering an animation correctly. The animation has a character holding an object in his hand (the object is parented to his hand).
If I render this animation using the animation button and selecting f.e. frame 165 to 400, the object sometimes leaves his hand in the rendered image ( with faster movement the problem is worse then with slow movement of the hand).
If I render this frame by frame (go to frame 165, press F12, save image, go to frame 166, f12, save, etc…) all images are correct and the object is always parented correctly.

Also in the viewport the object is always parented correctly.

I have the feeling there is some setting I am missing which generates this behaviour, however I am not able to find out what it is. I am using blender 2.67.

Does anybody know what might be causing this?

Thanks for your help

The same problem occurs if I render the animation from the command line. Interestingly, if I render a single frame using the command line, the problem is there as well.

Dear Blender user.
My name is Albert, I have problem with Blender Render, because when I render some frame of animations which have bone constraint and child of on it, the value of influence always change their number constantly by themselves, even though I have already set to certain number and also have insert keyframe it. Please, anyone can give me a kind of solution about that ?