diff --git a/chapter06/groff.xml b/chapter06/groff.xml
index 821a3e54e..aad0cbf85 100644
--- a/chapter06/groff.xml
+++ b/chapter06/groff.xml
@@ -53,9 +53,9 @@
 
 <screen><userinput remap="configure">PAGE=<replaceable>&lt;paper_size&gt;</replaceable> ./configure --prefix=/usr</userinput></screen>
 
-    <para>Compile the package:</para>
+    <para>This package does not support parallel build. Compile the package:</para>
 
-<screen><userinput remap="make">make</userinput></screen>
+<screen><userinput remap="make">make -j1</userinput></screen>
 
     <para>This package does not come with a test suite.</para>