diff --git a/chapter05/grep-inst.xml b/chapter05/grep-inst.xml
index 7b5c12b79..4a856e361 100644
--- a/chapter05/grep-inst.xml
+++ b/chapter05/grep-inst.xml
@@ -6,7 +6,7 @@ Install Grep by running the following commands:
 </para>
 
 <blockquote><literallayout>
-	<userinput>export CPPFLAGS=-Dre_max_failures=re_max_failures2 
+	<userinput>export CPPFLAGS=-Dre_max_failures=re_max_failures2
 		&amp;&amp;</userinput>
 	<userinput>./configure --prefix=$LFS/usr --disable-nls
 		 &amp;&amp;</userinput>
diff --git a/chapter06/groff-inst.xml b/chapter06/groff-inst.xml
index fba45efff..1bdbfd3fa 100644
--- a/chapter06/groff-inst.xml
+++ b/chapter06/groff-inst.xml
@@ -6,8 +6,8 @@ Install Groff by running the following commands:
 </para>
 
 <blockquote><literallayout>
-	<userinput>CXXFLAGS=-Dstrerror=strerror ./configure --prefix=/usr
-		&amp;&amp;</userinput>
+	<userinput>CXXFLAGS="-Dstrerror=strerror $CXXFLAGS" ./configure
+		--prefix=/usr &amp;&amp;</userinput>
 	<userinput>make &amp;&amp;</userinput>
 	<userinput>make install</userinput>
 </literallayout></blockquote>