Update to work with erlang23

- make sure it compiles with erl23.

rebar.config

@@ -25,7 +25,9 @@
     {"darwin10.*-32$", "CXXFLAGS", "-m32"},
     {"darwin10.*-32$", "LDFLAGS", "-arch i386"},
 
-    {"win32", "CXXFLAGS", "$CXXFLAGS /O2 /DNDEBUG"}
+    {"win32", "CXXFLAGS", "$CXXFLAGS /O2 /DNDEBUG"},
+
+    {"ERL_LDFLAGS"  , " -L$ERL_EI_LIBDIR -lei"}
 ]}.
 
 {erl_opts, [