I have had some limited sucess with the problem you are talking about by doing the following,
in poser select the object with the grouping tool, add a group that contains everything, and then "weld group". it will ask you to set a welding tolerance, you should increase this incramentally until it holds together, the big problem with this method is that the higher the welding tolerance, the more the object will begin to deform, so for somethings its no good, but this worked for me on hongyus t-shirt, which otherwise did not hold together.