Problem with Gus

I have a slight problem with Gus. When I append him from another file, and I move his arms with pose mode, the middle always splits. I tried the Recal norms button but that doesn’t work. Any ideas?

Thanks.

Select the 2 edgeloops (rows of verts) in the center common to both halves in Edit mode and do W >> Remove doubles. Then Ctrl-N to point all normals outside.

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