diff --git a/core/src/main/java/org/apache/struts2/StrutsConstants.java b/core/src/main/java/org/apache/struts2/StrutsConstants.java
index 44efda5ba..651e02559 100644
--- a/core/src/main/java/org/apache/struts2/StrutsConstants.java
+++ b/core/src/main/java/org/apache/struts2/StrutsConstants.java
@@ -145,4 +145,6 @@ public final class StrutsConstants {
 
     /** The name of the xwork converter implementation */
     public static final String STRUTS_XWORKCONVERTER = "struts.xworkConverter";
+
+    public static final String STRUTS_ALWAYS_SELECT_FULL_NAMESPACE = "struts.mapper.alwaysSelectFullNamespace";
 }
diff --git a/core/src/main/java/org/apache/struts2/dispatcher/mapper/DefaultActionMapper.java b/core/src/main/java/org/apache/struts2/dispatcher/mapper/DefaultActionMapper.java
index df25d59a1..f334c87d4 100644
--- a/core/src/main/java/org/apache/struts2/dispatcher/mapper/DefaultActionMapper.java
+++ b/core/src/main/java/org/apache/struts2/dispatcher/mapper/DefaultActionMapper.java
@@ -173,6 +173,8 @@ public class DefaultActionMapper implements ActionMapper {
     private boolean allowDynamicMethodCalls = true;
 
     private boolean allowSlashesInActionNames = false;
+    
+    private boolean alwaysSelectFullNamespace = false;
 
     private PrefixTrie prefixTrie = null;
     
@@ -243,6 +245,11 @@ public class DefaultActionMapper implements ActionMapper {
     public void setSlashesInActionNames(String allow) {
         allowSlashesInActionNames = "true".equals(allow);
     }
+    
+    @Inject(StrutsConstants.STRUTS_ALWAYS_SELECT_FULL_NAMESPACE)
+    public void setAlwaysSelectFullNamespace(String val) {
+        this.alwaysSelectFullNamespace = "true".equals(val);
+    }
 
     @Inject
     public void setContainer(Container container) {
@@ -264,7 +271,7 @@ public class DefaultActionMapper implements ActionMapper {
             return null;
         }
 
-        parseNameAndNamespace(uri, mapping, configManager.getConfiguration());
+        parseNameAndNamespace(uri, mapping, configManager);
 
         handleSpecialParameters(request, mapping);
 
@@ -330,7 +337,7 @@ public class DefaultActionMapper implements ActionMapper {
      *            The action mapping to populate
      */
     void parseNameAndNamespace(String uri, ActionMapping mapping,
-            Configuration config) {
+            ConfigurationManager configManager) {
         String namespace, name;
         int lastSlash = uri.lastIndexOf("/");
         if (lastSlash == -1) {
@@ -342,7 +349,13 @@ public class DefaultActionMapper implements ActionMapper {
             // namespace anyway if not found in root namespace.
             namespace = "/";
             name = uri.substring(lastSlash + 1);
+        } else if (alwaysSelectFullNamespace) {
+            // Simply select the namespace as everything before the last slash
+            namespace = uri.substring(0, lastSlash);
+            name = uri.substring(lastSlash + 1);
         } else {
+            // Try to find the namespace in those defined, defaulting to ""
+            Configuration config = configManager.getConfiguration();
             String prefix = uri.substring(0, lastSlash);
             namespace = "";
             // Find the longest matching namespace, defaulting to the default
diff --git a/core/src/main/resources/org/apache/struts2/default.properties b/core/src/main/resources/org/apache/struts2/default.properties
index 2c0420fc0..694e71b25 100644
--- a/core/src/main/resources/org/apache/struts2/default.properties
+++ b/core/src/main/resources/org/apache/struts2/default.properties
@@ -161,4 +161,7 @@ struts.templateEngines=ftl,jsp,vm
 ### A list of tag libraries available
 struts.tagLibraries=s
 
+### Whether to always select the namespace to be everything before the last slash or not
+struts.mapper.alwaysSelectFullNamespace=false
+
 ### END SNIPPET: complete_file
diff --git a/core/src/test/java/org/apache/struts2/dispatcher/mapper/DefaultActionMapperTest.java b/core/src/test/java/org/apache/struts2/dispatcher/mapper/DefaultActionMapperTest.java
index bcdaac391..0c3f58112 100644
--- a/core/src/test/java/org/apache/struts2/dispatcher/mapper/DefaultActionMapperTest.java
+++ b/core/src/test/java/org/apache/struts2/dispatcher/mapper/DefaultActionMapperTest.java
@@ -154,6 +154,22 @@ public class DefaultActionMapperTest extends StrutsTestCase {
         assertEquals("actionName", mapping.getName());
         assertNull(mapping.getMethod());
     }
+    
+    public void testGetMappingWithUnknownNamespaceButFullNamespaceSelect() throws Exception {
+        setUp();
+        req.setupGetRequestURI("/bo/foo/actionName.action");
+        req.setupGetServletPath("/bo/foo/actionName.action");
+        req.setupGetAttribute(null);
+        req.addExpectedGetAttributeName("javax.servlet.include.servlet_path");
+
+        DefaultActionMapper mapper = new DefaultActionMapper();
+        mapper.setAlwaysSelectFullNamespace("true");
+        ActionMapping mapping = mapper.getMapping(req, configManager);
+
+        assertEquals("/bo/foo", mapping.getNamespace());
+        assertEquals("actionName", mapping.getName());
+        assertNull(mapping.getMethod());
+    }
 
     public void testGetUri() throws Exception {
         req.setupGetParameterMap(new HashMap());
@@ -204,7 +220,7 @@ public class DefaultActionMapperTest extends StrutsTestCase {
         ActionMapping actionMapping = new ActionMapping();
 
         DefaultActionMapper defaultActionMapper = new DefaultActionMapper();
-        defaultActionMapper.parseNameAndNamespace("someAction", actionMapping, config);
+        defaultActionMapper.parseNameAndNamespace("someAction", actionMapping, configManager);
 
         assertEquals(actionMapping.getName(), "someAction");
         assertEquals(actionMapping.getNamespace(), "");
@@ -214,7 +230,7 @@ public class DefaultActionMapperTest extends StrutsTestCase {
         ActionMapping actionMapping = new ActionMapping();
 
         DefaultActionMapper defaultActionMapper = new DefaultActionMapper();
-        defaultActionMapper.parseNameAndNamespace("/someAction", actionMapping, config);
+        defaultActionMapper.parseNameAndNamespace("/someAction", actionMapping, configManager);
 
         assertEquals(actionMapping.getName(), "someAction");
         assertEquals(actionMapping.getNamespace(), "/");
@@ -224,7 +240,7 @@ public class DefaultActionMapperTest extends StrutsTestCase {
         ActionMapping actionMapping = new ActionMapping();
 
         DefaultActionMapper defaultActionMapper = new DefaultActionMapper();
-        defaultActionMapper.parseNameAndNamespace("/my/someAction", actionMapping, config);
+        defaultActionMapper.parseNameAndNamespace("/my/someAction", actionMapping, configManager);
 
         assertEquals(actionMapping.getName(), "someAction");
         assertEquals(actionMapping.getNamespace(), "/my");
@@ -235,7 +251,7 @@ public class DefaultActionMapperTest extends StrutsTestCase {
 
         DefaultActionMapper defaultActionMapper = new DefaultActionMapper();
         defaultActionMapper.setSlashesInActionNames("false");
-        defaultActionMapper.parseNameAndNamespace("/foo/someAction", actionMapping, config);
+        defaultActionMapper.parseNameAndNamespace("/foo/someAction", actionMapping, configManager);
 
         assertEquals(actionMapping.getName(), "someAction");
         assertEquals(actionMapping.getNamespace(), "");
@@ -246,7 +262,7 @@ public class DefaultActionMapperTest extends StrutsTestCase {
 
         DefaultActionMapper defaultActionMapper = new DefaultActionMapper();
         defaultActionMapper.setSlashesInActionNames("true");
-        defaultActionMapper.parseNameAndNamespace("/foo/someAction", actionMapping, config);
+        defaultActionMapper.parseNameAndNamespace("/foo/someAction", actionMapping, configManager);
 
         assertEquals(actionMapping.getName(), "foo/someAction");
         assertEquals(actionMapping.getNamespace(), "");
diff --git a/plugins/codebehind/src/main/resources/struts-plugin.xml b/plugins/codebehind/src/main/resources/struts-plugin.xml
index 1b8a7a72b..21afbe86a 100644
--- a/plugins/codebehind/src/main/resources/struts-plugin.xml
+++ b/plugins/codebehind/src/main/resources/struts-plugin.xml
@@ -9,6 +9,7 @@
 
     <constant name="struts.codebehind.pathPrefix" value="/"/>
     <constant name="struts.codebehind.defaultPackage" value="codebehind-default"/>
+    <constant name="struts.mapper.alwaysSelectFullNamespace" value="true" />
 
     <package name="codebehind-default" extends="struts-default">
     </package>