diff --git a/attachmentstrategy.cpp b/attachmentstrategy.cpp
index ca66ef7ee..0405106b9 100644
--- a/attachmentstrategy.cpp
+++ b/attachmentstrategy.cpp
@@ -52,6 +52,8 @@ namespace KMail {
     const char * name() const { return "iconic"; }
     const AttachmentStrategy * next() const { return smart(); }
     const AttachmentStrategy * prev() const { return hidden(); }
+
+    bool inlineNestedMessages() const { return false; }
   };
 
   //
@@ -70,6 +72,8 @@ namespace KMail {
     const char * name() const { return "smart"; }
     const AttachmentStrategy * next() const { return inlined(); }
     const AttachmentStrategy * prev() const { return iconic(); }
+
+    bool inlineNestedMessages() const { return true; }
   };
 
   //
@@ -87,6 +91,8 @@ namespace KMail {
     const char * name() const { return "inlined"; }
     const AttachmentStrategy * next() const { return hidden(); }
     const AttachmentStrategy * prev() const { return smart(); }
+
+    bool inlineNestedMessages() const { return true; }
   };
 
   //
@@ -104,6 +110,8 @@ namespace KMail {
     const char * name() const { return "hidden"; }
     const AttachmentStrategy * next() const { return iconic(); }
     const AttachmentStrategy * prev() const { return inlined(); }
+
+    bool inlineNestedMessages() const { return false; }
   };
 
 
diff --git a/attachmentstrategy.h b/attachmentstrategy.h
index 8eb13e3d1..d47f0380b 100644
--- a/attachmentstrategy.h
+++ b/attachmentstrategy.h
@@ -55,9 +55,19 @@ namespace KMail {
     static const AttachmentStrategy * inlined();
     static const AttachmentStrategy * hidden();
 
+    //
+    // Navigation methods:
+    //
+
     virtual const char * name() const = 0;
     virtual const AttachmentStrategy * next() const = 0;
     virtual const AttachmentStrategy * prev() const = 0;
+
+    //
+    // Bahavioural:
+    //
+
+    virtual bool inlineNestedMessages() const = 0;
   };
 
 }; // namespace KMail