--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/run/mini/interface5.d	Mon Jan 10 19:47:18 2011 +0100
@@ -0,0 +1,34 @@
+module interface5;
+
+extern(C) int printf(char*,...);
+
+interface I
+{
+    void func();
+}
+
+class C : I
+{
+    int i;
+    void func()
+    {
+        printf("C\n");
+        i++;
+    }
+}
+
+void main()
+{
+    C c = new C;
+    c.func();
+    {
+        I i = c;
+        i.func();
+
+        C c2 = cast(C)i;
+        c2.func();
+
+        c.func();
+        assert(c.i == 4);
+    }
+}