diff --git a/jsdoc.conf.json b/jsdoc.conf.json
index 7647c39..55b83c9 100644
--- a/jsdoc.conf.json
+++ b/jsdoc.conf.json
@@ -18,7 +18,7 @@
     "dateFormat"       : "DD / MM / YYYY",
     "outputSourceFiles": false,
     "outputSourcePath" : false,
-    "systemName"       : "ES5Class",
+    "systemName"       : "Prototypal class inheritance for Node.js and the browser",
     "footer"           : "",
     "copyright"        : "",
     "navType"          : "inline",
diff --git a/test/class-test.js b/test/class-test.js
index c92ddd2..7e36040 100644
--- a/test/class-test.js
+++ b/test/class-test.js
@@ -1578,6 +1578,33 @@ describe('ES5Class', function (){
 
   });
 
+  it('toString and valueOf', function(){
+    var Cls = ES5Class.$define('Cls', {
+      toString: function(){
+        return 'prototype';
+      }
+    }, {
+      toString: function(){
+        return 'static';
+      }
+    });
+
+    expect('' + Cls()).to.be('prototype');
+    expect('' + Cls).to.be('static');
+    Cls.$implement({
+      valueOf: function(){
+        return 'static valueOf';
+      }
+    });
+    Cls.$include({
+      valueOf: function(){
+        return 'prototype valueOf';
+      }
+    });
+    expect('' + Cls()).to.be('prototype valueOf');
+    expect('' + Cls).to.be('static valueOf');
+  });
+
   it('constructor', function (){
     expect(typeof Bird).to.be('function');
     expect(Bird.$create).to.be.a('function');