diff --git a/Tools/javascript/javascript.cxx b/Tools/javascript/javascript.cxx
index a1e6c9984..82e94f434 100644
--- a/Tools/javascript/javascript.cxx
+++ b/Tools/javascript/javascript.cxx
@@ -29,15 +29,9 @@ int main(int argc, char* argv[]) {
       std::string module_name(argv[idx]);
       module_names.push_back(module_name);
     } else if(strcmp(argv[idx], "-v8") == 0) {
-#ifndef USE_V8
-      std::cerr << "V8 support is not enabled" << std::endl;
-      exit(-1);
-#endif
+        shell = JSShell::Create(JSShell::V8);
     } else if(strcmp(argv[idx], "-jsc") == 0) {
-#ifndef USE_JSC
-      std::cerr << "JSC support is not enabled" << std::endl;
-      exit(-1);
-#endif
+        shell = JSShell::Create(JSShell::JSC);
     } else if(strcmp(argv[idx], "-i") == 0) {
       interactive = true;
     } else {
@@ -45,7 +39,9 @@ int main(int argc, char* argv[]) {
     }
   }
 
-  shell = JSShell::Create();
+  if (shell == 0) {
+    shell = JSShell::Create();
+  }
 
   bool failed = false;
   for(std::vector<std::string>::iterator it = module_names.begin();
diff --git a/Tools/javascript/js_shell.cxx b/Tools/javascript/js_shell.cxx
index b2b8672a6..8762fbff5 100644
--- a/Tools/javascript/js_shell.cxx
+++ b/Tools/javascript/js_shell.cxx
@@ -15,6 +15,8 @@
 #error "implement dll loading"
 #endif
 
+
+
 JSShell::~JSShell() {
 
   for(std::vector<HANDLE>::iterator it = loaded_modules.begin();
@@ -93,3 +95,32 @@ std::string JSShell::ReadFile(const std::string& fileName)
 
   return script;
 }
+
+#ifdef ENABLE_JSC
+extern JSShell* JSCShell_Create();
+#endif
+#ifdef ENABLE_V8
+extern JSShell* V8Shell_Create();
+#endif
+
+typedef JSShell*(*ShellFactory)();
+
+static ShellFactory js_shell_factories[2] = {
+#ifdef ENABLE_JSC
+JSCShell_Create,
+#else
+0,
+#endif
+#ifdef ENABLE_V8
+V8Shell_Create,
+#else
+0,
+#endif
+};
+
+JSShell *JSShell::Create(Engine engine) {
+  if(js_shell_factories[engine] == 0) {
+    throw "Engine not supported.";
+  }
+  return js_shell_factories[engine]();
+}
diff --git a/Tools/javascript/js_shell.h b/Tools/javascript/js_shell.h
index 830873f0d..54f55b69d 100644
--- a/Tools/javascript/js_shell.h
+++ b/Tools/javascript/js_shell.h
@@ -10,7 +10,7 @@ class JSShell {
 
 public:
   enum Engine {
-    JSC,
+    JSC = 0,
     V8
   };
 
@@ -20,7 +20,7 @@ public:
 
   virtual ~JSShell() = 0;
 
-  static JSShell* Create();
+  static JSShell* Create(Engine engine = JSC);
 
   bool ImportModule(const std::string& name);
 
@@ -46,6 +46,4 @@ protected:
 
 };
 
-typedef JSShell* (*JSShellFactory)();
-
 #endif // JS_SHELL_H
diff --git a/Tools/javascript/jsc_shell.cxx b/Tools/javascript/jsc_shell.cxx
index c069b5c65..ee95e04a5 100644
--- a/Tools/javascript/jsc_shell.cxx
+++ b/Tools/javascript/jsc_shell.cxx
@@ -160,6 +160,6 @@ void JSCShell::PrintError(JSContextRef ctx, JSValueRef err, const std::string& n
   std::cerr << name << ":" << line << ":" << errMsg << std::endl;
 }
 
-JSShell* JSShell::Create() {
+JSShell* JSCShell_Create() {
   return new JSCShell();
 }
diff --git a/Tools/javascript/v8_shell.cxx b/Tools/javascript/v8_shell.cxx
index 8b45ac0d6..0055bad98 100755
--- a/Tools/javascript/v8_shell.cxx
+++ b/Tools/javascript/v8_shell.cxx
@@ -285,6 +285,6 @@ const char* V8Shell::ToCString(const v8::String::Utf8Value& value) {
   return *value ? *value : "<string conversion failed>";
 }
 
-JSShell* JSShell::Create() {
+JSShell* V8Shell_Create() {
   return new V8Shell();
 }