SWT Group Border is invisible unless resize the preference oage
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I added a component on top area of SWT PreferencePage , and then added a group and then again added few components after the group.
First time opening is fine and then again once we reopen , I found that the group is not visible only blank space is there and once we resize the preference page it again fine.
But if I remove the top components and add those inside the group , then everything works fine.

WITH GROUP-
![enter image description here][1]


without group
![enter image description here][2]


  [1]: http://i.stack.imgur.com/vUVsC.png
  [2]: http://i.stack.imgur.com/hS2Uz.png

So its clear that Group has gone missing second time and once we resize its fine.
What is the problem