diff --git a/jnlp/plugin.jelly b/jnlp/plugin.jelly
index fa902059..eead038b 100644
--- a/jnlp/plugin.jelly
+++ b/jnlp/plugin.jelly
@@ -280,7 +280,10 @@
         <!-- =========================== -->
         <!-- Copy jars in jnlp directory -->
         <!-- =========================== -->
-        <ant:available file="${maven.jnlp.signjar.store}" property="maven.jnlp.store.exists"/>
+        <j:set var="storeFileName" value="${maven.jnlp.signjar.store}"/>
+        <j:if test="${!empty(storeFileName)}">
+          <ant:available file="${maven.jnlp.signjar.store}" property="maven.jnlp.store.exists"/>
+        </j:if>
         <j:choose>
           <j:when test="${maven.jnlp.store.exists}">