Is *Loc* regular?

I have been wondering lately whether every regular monomorphism of the category of frames is universal (= pushout stable). But it is not hard to see (using, e.g., Kelly's "Monomorphisms, epimorphisms, and pull-backs" J.Austr.Math.Soc. 9, 1969) that this is equivalent to the question of whether the category of locales is a regular category. Does anyone have an answer to this question? --Todd Wilson