diff --git a/qt/qt4/qt4.conf b/qt/qt4/qt4.conf
index 4b2f329ce..05f05c280 100644
--- a/qt/qt4/qt4.conf
+++ b/qt/qt4/qt4.conf
@@ -23,12 +23,25 @@ if [ "$prefix" = "usr" ]; then
 fi
 
 pkg_qt4_preconf() {
+	# fix X11 prefix to get correct pkg-config files
+	echo 'Fixing X11 prefix ...'
+	for x in $(egrep -rl X11R6 *) ; do sed -i -e "s,usr/X11R6,$(pkgprefix libx11)," $x ; done
+
 	# helping the linker to find libraries
 	QTDIR=$PWD
 	var_insert LD_LIBRARY_PATH ':' "$QTDIR/lib"
 	var_insert PATH ':' "$QTDIR/bin"
 	export QTDIR LD_LIBRARY_PATH PATH
 
+	QMAKE_INCDIR_X11="$( pkgprefix includedir libx11 )"
+	QMAKE_LIBDIR_X11="$( pkgprefix libdir libx11 )"
+
+#	cat > .qmake.vars <<-EOT
+#QMAKE_INCDIR_X11="$QMAKE_INCDIR_X11"
+#QMAKE_LIBDIR_X11="$QMAKE_LIBDIR_X11"
+#EOT
+#	cp .qmake.vars{,.sde}
+
 	# Somehow config options get removed if using the standard config
 	# handling. So we use a custom one here.
 	./configure $confopt