AO Bake has random black pixels on some faces This is what my baked AO texture looks like (not in all places -- for most faces it looks fine):



What is the cause of this?  What can I do to resolve it?  I do not have any overlapping UVs and my mesh is manifold.

Here is the mesh if you would like to take a look: http://pasteall.org/blend/34604

Thank you all for your help!
The problem was caused by other objects overlapping the object that I wanted to bake.  When modelling I used the boolean modifier with some other objects and hid the old objects after applying it.  By deleting the old objects the bake worked perfectly.

Thanks to Leon Cheung and MarcClintDion for their help!