Well, I looked more at this yesterday evening. I ran several hardware
tests programs which didn't find anything wrong on my box. Then I opened
it and removed and put back the SIMMS.
I couldn't reproduce the pmap_zero_page panic after that, but still got a core
dumps from cc1.

Unless someone else get this, I think this can be classified as
"hardware problem". Sorry for the noise, and thank to the people (Chuck
and Jason) who spent some time on it.

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Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
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