Don't "exit" or "close" the Gmail application.
Either hit the escape key (just right of the track ball) or the red button (top row right of trackball.)
Hope this helps...
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There is a delay but then even w/ Gmail using BIS there is no guarentee you get emails instantly.
But I have never experienced a 15 minute delay. It's usually 4 to 7 minutes. But that being said, YMMV.
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