Fixed toolbar page on Android 4.0.3

Fixed toolbar page on Android 4.0.3

Please tell me how to resolve those 2 problems.

Those problems has happend on Android 4.0.3 native browser.
And fixed toolbar page cause those problems.
In short, if page container includes [<div data-role="header" data-position="fixed"></div>], those 2 problems happen.
 
1. navigation to fixed toolbar page

      navigation to fixed toolbar page cause twice white flash (onece white flash is expected).
      current page →　white flash →　current page →　white flash →　fixed toolbar page
 
2. pinch out can't expand fixed toolbar page
      In fixed toolbar page, I pinched out to expand window, but It was failed to expand.
 
Thanks.