blender mesh rigging problem

[IIianII]

Hello

I uploaded a shirt which I created from MD and imported to blender for sl rigging.

I noticed the neck area moves with the shoulder bones and I can't figure out how to fix it. I use the avastar plugin to rig it btw. I select the shirt along with the loops to bind it to armature. after that I deselect everything, shift click, selects the avatar along with the shirt and loops once more and click Apply weights. I found out that this procedure somehow makes the shirt move smoothly esp on the stomach area. without it, it makes the texture all look crappy when uploaded.

but then the downside is that the collar area moves with the shoulder, so when my avatar raise his hands or does the same type of pose, it burries the collar in my avatar's neck.





What should I do? all mesh experts please enlighten me. I'm still new to this

Thank you