*** biconnected_components.hpp	Wed Oct 19 13:47:01 2011
--- /usr/local/include/boost/graph/biconnected_components.hpp	Wed Oct 19 13:46:35 2011
***************
*** 77,83 ****
        void back_edge(const Edge& e, Graph& g)
        {
          BOOST_USING_STD_MIN();
!         if(!S.empty() && source(S.top(),g) != target(e,g)) {
            S.push(e);
            put(lowpt, source(e, g),
                min BOOST_PREVENT_MACRO_SUBSTITUTION(get(lowpt, source(e, g)),
--- 77,84 ----
        void back_edge(const Edge& e, Graph& g)
        {
          BOOST_USING_STD_MIN();
! 
!         if ( target(e, g) != get(pred, source(e, g)) ) {
            S.push(e);
            put(lowpt, source(e, g),
                min BOOST_PREVENT_MACRO_SUBSTITUTION(get(lowpt, source(e, g)),