diff --git a/.travis.yml b/.travis.yml
index 1253fc5c9..2a3bdc000 100755
--- a/.travis.yml
+++ b/.travis.yml
@@ -49,6 +49,7 @@ addons:
     - libbz2-dev
     - libpcre3-dev
     - swig
+    - libxml2-utils
 
 before_install:
   - lsb_release -a
diff --git a/Makefile b/Makefile
index a4089f8ff..a5eee18ff 100644
--- a/Makefile
+++ b/Makefile
@@ -442,6 +442,8 @@ $(polxml): $(layerxml) $(tunxml) $(boolxml)
 	$(verbose) echo '</policy>' >> $@
 	$(verbose) if test -x $(XMLLINT) && test -f $(xmldtd); then \
 		$(XMLLINT) --noout --path $(dir $(xmldtd)) --dtdvalid $(xmldtd) $@ ;\
+		else \
+		echo "$@ XML validation not run. Please install the xmllint tool." ;\
 	fi
 
 xml: $(polxml)