-

diff --git a/build_config.rb b/build_config.rb
index 4e3e90a..047e393 100644
--- a/build_config.rb
+++ b/build_config.rb
@@ -8,6 +8,10 @@
     cc.flags << ENV['NGX_MRUBY_CFLAGS'] if ENV['NGX_MRUBY_CFLAGS'] 
   end
 
+  conf.linker do |linker|
+    linker.option_library << ' -lstdc++'
+  end
+
   #
   # Recommended for ngx_mruby
   #
@@ -32,6 +36,7 @@
   conf.gem './mrbgems/ngx_mruby_mrblib'
   conf.gem './mrbgems/rack-based-api'
 
+  conf.gem :github => 'kjunichi/mruby-mrmagick'
   # use memcached
   # conf.gem :github => 'matsumotory/mruby-memcached'
 
diff --git a/src/http/ngx_http_mruby_filter.c b/src/http/ngx_http_mruby_filter.c
index 91e8e00..e90642d 100644
--- a/src/http/ngx_http_mruby_filter.c
+++ b/src/http/ngx_http_mruby_filter.c
@@ -34,7 +34,7 @@ static mrb_value ngx_mrb_set_filter_body(mrb_state *mrb, mrb_value self)
     body = mrb_funcall(mrb, body, "to_s", 0, NULL);
   }
 
-  ctx->body = (u_char *)mrb_str_to_cstr(mrb, body);
+  ctx->body = (u_char *)RSTRING_PTR(body);
   ctx->body_length = RSTRING_LEN(body);
 
   return mrb_fixnum_value(ctx->body_length);