Mesh problems (Was Garbage Collection)

OK, these lines


	for Patch in BaseMeshes:
		Mesh = Patch.getData()
		if (TPlaneMap.val==1):
			TerraFormF(Mesh)
		else:
			TerraFormS(Mesh)
		print "Terraformed plot "
		Mesh.mode = 260
		NMesh.PutRaw(Mesh,Patch.getName())	

Makes Blender 2.28c crash at the second time or so

ANd causes Patch to be *duplicated, not updated
in its Mesh data in the current CVS build!

Any ideas?

Stefano