qt Add support for exceptions - like catching them inside the event loop (recommended by Nokia) Enable dev-libs/glib eventloop support Enable the Qt3Support libraries for Qt4. Note that this does not mean you can compile pure Qt3 programs with Qt4. Use the alternative raster graphicssystem as default rendering engine Build the new 'trace' graphicsssytem engine which allows to record all drawing operations into a trace buffer. Later it can be replayed with the qttracereplay utility