REG: Components added to the Window are not layed out properly when showing from an applet, Sol10

I am launching a frame and a couple of windows from an applet. A button is added to the 'Center' of the border layout in each of these windows. I expect the button to take the size of the whole window, as the case for any component added to the 'center' of BorderLayout. But on SolSparc10, the button size is half of the window and it is intermittent. Sometimes, it appears correctly. Sometimes one of the windows is showing it properly.

This is reproducible only when running as an applet and not reproducible in the application mode. This is reproducible only on SolSparc10-JDS and not reproducible on Win32. This is reproducible with Mustang-b73 and not reproducible on Tiger-FCS. Hence this is a regression in Mustang.

I have attached a sample test which can be run as an applet as well as application. Open the HTML file in Mozilla 1.7 browser on SolSparc10-JDS. If the buttons on each of the windows is not taking the size of the respective windows, the bug is reproduced. I have attached a screenshot of the same.