diff --git a/build.xml b/build.xml
index 48dc835e..34363abe 100644
--- a/build.xml
+++ b/build.xml
@@ -502,7 +502,8 @@
 						<include name="**/*.jar"/>
 					</fileset>
 				</classpath>
-				<jvmarg value="-Djava.endorsed.dirs=${tools.xmltool}/endorsed"/>
+				<jvmarg value="-Djava.endorsed.dirs=${tools.xmltool}/endorsed"/>
+				<jvmarg value="-Dorg.opensaml.xml.util.XmlTool.home=${tools.xmltool}"/>
 				<args/>
 				<arg value="--validateSchema"/>
 				<arg value="--schemaDirectory"/>