diff --git a/general/genlib/qca.xml b/general/genlib/qca.xml
index 9682116ad4..7c8c3eddc5 100644
--- a/general/genlib/qca.xml
+++ b/general/genlib/qca.xml
@@ -94,17 +94,29 @@
 
 <screen><userinput>sed -i 's/BSD/DEFAULT/' CMakeLists.txt</userinput></screen>
 
+    <para>This package can be built against <xref linkend="qt4"/> or <xref linkend="qt5"/>.
+    If using qt4, run:</para>
+
+<screen><userinput>QT_DIR=&qt4-dir; &amp;&amp;
+QT4_BUILD=ON</userinput></screen>
+
+    <para>If using qt5, run:</para>
+
+<screen><userinput>QT_DIR=&qt5-dir; &amp;&amp;
+QT4_BUILD=OFF</userinput></screen>
+
     <para>Install <application>Qca</application> by running the following
     commands:</para>
 
 <screen><userinput>mkdir build &amp;&amp;
 cd    build &amp;&amp;
 
-cmake -DCMAKE_INSTALL_PREFIX=&qt4-dir;            \
+cmake -DCMAKE_INSTALL_PREFIX=$QT_DIR            \
       -DCMAKE_BUILD_TYPE=Release                \
-      -DQT4_BUILD=ON                            \
+      -DQT4_BUILD=$QT4_BUILD                    \
       -DQCA_MAN_INSTALL_DIR:PATH=/usr/share/man \
       ..                                        &amp;&amp;
+unset QT_DIR QT4_BUILD                          &amp;&amp;
 
 make</userinput></screen>