add missing var

Author: yaronn

lib/signed-xml.js

@@ -322,7 +322,7 @@ SignedXml.prototype.validateReferences = function(doc) {
       var num_elements_for_id = 0;
       for (var index in this.idAttributes) {
         if (!this.idAttributes.hasOwnProperty(index)) continue;
-        tmp_elem = select(doc, "//*[@*[local-name(.)='" + this.idAttributes[index] + "']='" + uri + "']")
+        var tmp_elem = select(doc, "//*[@*[local-name(.)='" + this.idAttributes[index] + "']='" + uri + "']")
         num_elements_for_id += tmp_elem.length;
         if (tmp_elem.length > 0) {
           elem = tmp_elem;