Nokia Qt/Diga released a few fixes for 4.8, including some for Symbian.
maybe they will be included in next firmware updates (if Nokia updates Symbian, but that's anther question ...) ?
Let's ignore sigining, certs, capabilties and installing on Z:\ etc., there's this tutorial http://qt-project.org/wiki/Building_...bian_3_Devices
latest public PDK is from Symbian^3 and really outdated, is there any chance that a Symbian developer with latest Belle PDK can build and share it for the community?
Qt is open source and there are still a lot of Symbian programmers which want latest fixes and updates but as far as I know we can't build it.