Rigging for male fitted mesh

[Psistorm Voxel]

Once again me, breaking things left and right it would seem.

The problem this time around is this. My avatar uses the default SL mesh, clipped and re-rigged/imported to enable use of materials on the default-ish SL body shape. I've conquered the rigging issues now, but one weird problem remains.

I did the male body the other day, and while it is on a female shape, everything looks fine. But the moment I transition to male, everything bulges out weirdly and deforms wrong.

Thus my question: How do I properly rig something to a male base shape? The skeletons and influences from the source files seemed to be identical as near as I could tell, so why is the male shape breaking things so badly? I want my head/hands/etc to also blend proper with the base SL avatar for this project, so their seams bulging out on a male shape is a pretty huge problem.