diff --git a/bin/addons/base/rng/view.rng b/bin/addons/base/rng/view.rng
index d822ed3c4ac..5a489a55936 100644
--- a/bin/addons/base/rng/view.rng
+++ b/bin/addons/base/rng/view.rng
@@ -280,6 +280,7 @@
     <rng:define name="separator">
         <rng:element name="separator">
             <rng:optional><rng:attribute name="colspan"/></rng:optional>
+            <rng:optional><rng:attribute name="rowspan"/></rng:optional>
             <rng:optional><rng:attribute name="string"/></rng:optional>
             <rng:optional><rng:attribute name="col"/></rng:optional>
             <rng:optional><rng:attribute name="select"/></rng:optional>