@Brice:
No, you can't do that selectively site by site yet you can lift off Google's red alerts altogether. Goto your Firefox' Tools->Options->Security tab and uncheck the "Block dangerous and deceptive content" box.
@Eros:
We had a couple similar problems with Google in the past too and it used to take them up to two weeks to remove their false positives. So we may have to be real patient. It make take that long in this particular case as well though I hope sincerely it won't.
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