mkdir -vp ${_builddir}
     cd ${_builddir}
     msg "Starting cmake..."
     cmake ${_source}/${_module}/ \
     -DCMAKE_INSTALL_PREFIX=${_prefix} \
     -DWITH_XINE=ON \
     -DBUILD_ALL=ON \
     -DCMAKE_SKIP_RPATH=ON
     make


[  9%] Built target amarokcore-static
[  9%] Building CXX object 
amarok/src/magnatunebrowser/CMakeFiles/magnatunebrowser-static.dir/magnatunelistviewitems.cpp.o
[ 10%] Generating pluginconfig.moc.cpp
/bin/sh: /trinity.source/amarok/amarok/src/plugin/pluginconfig.h: 
Permission denied
make[2]: *** [amarok/src/plugin/pluginconfig.moc.cpp] Error 126
make[1]: *** [amarok/src/plugin/CMakeFiles/plugin-static.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....

Looks like it come from this 
/trinity.source/applications/amarok/amarok/src/plugin/CmakeLists.txt


##### plugin (static) ###########################

add_custom_command( OUTPUT pluginconfig.moc.cpp
   COMMAND
     ${TQT_TMOC_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/pluginconfig.h 
-o pluginconfig.moc.cpp
   DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/pluginconfig.h )

tde_add_library( plugin STATIC_PIC
   SOURCES plugin.cpp pluginconfig.moc.cpp
)

Is this trying to write the file into the source directory or the out of 
source build directory?