Merge pull request #146 from apache/action-prefix-clearance
Adds a note about action: prefix configuration
diff --git a/source/core-developers/action-mapper.md b/source/core-developers/action-mapper.md
index 8c8ffa1..c42aae9 100644
--- a/source/core-developers/action-mapper.md
+++ b/source/core-developers/action-mapper.md
@@ -43,6 +43,19 @@
the extension form (eg: `foo!bar.action`) or in the prefix form (eg: `action:foo!bar`). This syntax tells this mapper
to map to the action named `foo` and the method `bar`.
+> NOTE: By default support for the `action:` prefix has been disabled since Struts 2.3.15.3, please use the below
+> constant to enable it:
+> - using `struts.properties`:
+> ```
+> struts.mapper.action.prefix.enabled=true
+> ```
+> - or using `struts.xml`:
+> ```
+> <constant name="struts.mapper.action.prefix.enabled" value="true"/>
+> ```
+>
+> See [S2-018](https://cwiki.apache.org/confluence/display/WW/S2-018) for more details.
+
### Method prefix
With method-prefix, instead of calling baz action's `execute()` method (by default if it isn't overridden in `struts.xml`
