diff --git a/src/docbkx/what-is-spring-ws.xml b/src/docbkx/what-is-spring-ws.xml
index 1af42604..82c48d01 100644
--- a/src/docbkx/what-is-spring-ws.xml
+++ b/src/docbkx/what-is-spring-ws.xml
@@ -79,9 +79,9 @@
     <section>
         <title>Runtime environment</title>
         <para>
-            Spring Web Services runs within a standard Java 1.3 Runtime Environment. It also supports Java 5.0, 
+            Spring Web Services runs within a standard Java 1.3 Runtime Environment. It also supports Java 5.0,
             although the Java types which are specific to this release are packaged in a separate modules with the 
-            suffix "tiger" in their JAR filename.
+            suffix "tiger" in their JAR filename. Note that the security module also requires Java 5.
         </para>
         <para>
             Spring-WS consists of a number of modules, which are described in the remainder of this section.