I am developing my first application with Qt for Symbian (using Qt 4.6.3 and Qt SDK from Nokia) and have encountered the following problem when testing on Nokia N8: edges of the window frames are corrupted. The problem is not appearing on a 5th edition device (5230). Most probably this is related to the fact that the window corners in the N8 theme are rounded and transparent. However they are not drawn transparent. The problem appears in message boxes, menus and dialog windows.
I tried to use a stylesheet for the dialog windows but this leads to rectangular windows with black background regardless of the current theme and even this bad workaround is not available for the message boxes and the menus.