The path to the Qt files are compiled into the qt lib and bin files. This path is in the file ${QTDIR}/src/tools/qconfig.cpp generated by the configure script. The current ebuild files for Qt do not pass -prefix ${QTBASE} to the configure script to set the compile in path correctly. This results in the path being set to the directory qt is compiled in. This problem only affects some of the tools in /usr/qt/3/bin: Qt Assistant looks for the documentation in the directory qt was compiled in. I
added this to most recent qt ebuilds (3.0.5-r2 and 3.1). thanks for submission.