diff --git a/doc/container.qbk b/doc/container.qbk
index e4e6e14..9b5ddd9 100644
--- a/doc/container.qbk
+++ b/doc/container.qbk
@@ -1218,6 +1218,7 @@ use [*Boost.Container]? There are several reasons for that:
 * Fixed bugs:
    * [@https://svn.boost.org/trac/boost/ticket/9481 Trac #9481: ['"Minor comment typo in Boost.Container"]].
    * [@https://svn.boost.org/trac/boost/ticket/11170 Trac #11170: ['"Doc slip for index_of"]].
+   * [@https://svn.boost.org/trac/boost/ticket/11802 Trac #11802: ['"Incorrect ordering after using insert() with ordered_range_t on a flat_multiset with a non-default sort order"]].
    * [@https://svn.boost.org/trac/boost/ticket/12177 Trac #12177: ['"vector::priv_merge uses unqualified uintptr_t"]].
    * [@https://svn.boost.org/trac/boost/ticket/12183 Trac #12183: ['"GCC 6.1 thinks boost::container::string violates strict aliasing"]].
    * [@https://svn.boost.org/trac/boost/ticket/12256 Trac #12256: ['"set<std::pair<int,int>>::insert cause compilation error in debug configuration in Visual Studio 2012"]].
diff --git a/include/boost/container/detail/flat_tree.hpp b/include/boost/container/detail/flat_tree.hpp
index 7b540fa..7ba35cc 100644
--- a/include/boost/container/detail/flat_tree.hpp
+++ b/include/boost/container/detail/flat_tree.hpp
@@ -483,7 +483,7 @@ class flat_tree
          >::type * = 0
       #endif
       )
-   {   this->m_data.m_vect.merge(first, last);   }
+   {   this->m_data.m_vect.merge(first, last, static_cast<const value_compare &>(this->m_data));   }
 
    template <class InIt>
    void insert_unique(ordered_unique_range_t, InIt first, InIt last
@@ -512,7 +512,7 @@ class flat_tree
          >::type * = 0
       #endif
       )
-   {   this->m_data.m_vect.merge_unique(first, last, value_compare());   }
+   {   this->m_data.m_vect.merge_unique(first, last, static_cast<const value_compare &>(this->m_data));   }
 
    #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)