diff --git a/doc/xdocs/building.html b/doc/xdocs/building.html
index c0503ee394..d1f68be177 100644
--- a/doc/xdocs/building.html
+++ b/doc/xdocs/building.html
@@ -111,7 +111,7 @@
   <p>If you get an <code>OutOfMemoryError</code>, simply execute the following before
 	calling Maven:</p>
 	<ol>
-		<pre>set MAVEN_OPTS=-Xmx1024m</pre>
+		<pre>set MAVEN_OPTS=-Xmx1024m -XX:MaxPermSize=512m</pre>
 	</ol>
   <p>If you get an <code>[ERROR] Invalid license: Invalid license file [E1202]</code>,
 	this is because the <code>maven-clover-plugin</code> is using an old version of