WW-5047 Avoids confusion about scope's default value
diff --git a/core/src/main/java/com/opensymphony/xwork2/config/providers/XmlConfigurationProvider.java b/core/src/main/java/com/opensymphony/xwork2/config/providers/XmlConfigurationProvider.java
index 04aad76..ce1587d 100644
--- a/core/src/main/java/com/opensymphony/xwork2/config/providers/XmlConfigurationProvider.java
+++ b/core/src/main/java/com/opensymphony/xwork2/config/providers/XmlConfigurationProvider.java
@@ -242,15 +242,19 @@
                         String onlyStatic = child.getAttribute("static");
                         String scopeStr = child.getAttribute("scope");
                         boolean optional = "true".equals(child.getAttribute("optional"));
-                        Scope scope = Scope.SINGLETON;
+                        Scope scope;
                         if ("prototype".equals(scopeStr)) {
                             scope = Scope.PROTOTYPE;
                         } else if ("request".equals(scopeStr)) {
                             scope = Scope.REQUEST;
                         } else if ("session".equals(scopeStr)) {
                             scope = Scope.SESSION;
+                        } else if ("singleton".equals(scopeStr)) {
+                            scope = Scope.SINGLETON;
                         } else if ("thread".equals(scopeStr)) {
                             scope = Scope.THREAD;
+                        } else {
+                            scope = Scope.SINGLETON;
                         }
 
                         if (StringUtils.isEmpty(name)) {