diff --git a/bloodhound_multiproduct/multiproduct/env.py b/bloodhound_multiproduct/multiproduct/env.py
index 87db30b..23a0b6d 100644
--- a/bloodhound_multiproduct/multiproduct/env.py
+++ b/bloodhound_multiproduct/multiproduct/env.py
@@ -365,6 +365,8 @@
                 g_env = env.parent if isinstance(env,
                                                  ProductEnvironment) else env
                 return f(self, g_env, *args, **kwargs)
+            __call__.clear = f.clear
+
             return __call__
 
         def product_env_keymap(args, kwds, kwd_mark):
@@ -397,6 +399,10 @@
     setup_participants = ExtensionPoint(trac.env.IEnvironmentSetupParticipant)
     multi_product_support_components = ExtensionPoint(ISupportMultiProductEnvironment)
 
+    @classmethod
+    def clear_env_cache(cls):
+        cls.__metaclass__.__call__.clear()
+
     @property
     def product_setup_participants(self):
         return [
diff --git a/bloodhound_multiproduct/multiproduct/hooks.py b/bloodhound_multiproduct/multiproduct/hooks.py
index a39571e..855a5ca 100644
--- a/bloodhound_multiproduct/multiproduct/hooks.py
+++ b/bloodhound_multiproduct/multiproduct/hooks.py
@@ -37,6 +37,8 @@
 
 class MultiProductEnvironmentFactory(EnvironmentFactoryBase):
     def open_environment(self, environ, env_path, global_env, use_cache=False):
+        # clearing product environment cache - bh:ticket:613
+        multiproduct.env.ProductEnvironment.clear_env_cache()
         environ.setdefault('SCRIPT_NAME', '')  # bh:ticket:594
 
         env = pid = product_path = None