diff --git a/configure.in b/configure.in
index 9f5baeb8..0b469490 100644
--- a/configure.in
+++ b/configure.in
@@ -109,6 +109,7 @@ BIRD_CHECK_TIME_T
 if test "$enable_debug" = yes ; then
 	AC_DEFINE(PATH_CONFIG_DIR, ".")
 	AC_DEFINE(DEBUGGING)
+	AC_CHECK_LIB(efence, malloc)
 else
 	AC_DEFINE_UNQUOTED(PATH_CONFIG_DIR, "$sysconfdir")
 fi
diff --git a/tools/Rules.in b/tools/Rules.in
index db94ba0f..36a6eece 100644
--- a/tools/Rules.in
+++ b/tools/Rules.in
@@ -18,6 +18,7 @@ dir-objs:=$(addprefix $(objdir)/,$(all-dirs))
 
 CPPFLAGS=-I$(root-rel) -I$(srcdir)
 CFLAGS=$(CPPFLAGS) @CFLAGS@
+LDFLAGS=@LIBS@
 CC=@CC@
 M4=@M4@
 BISON=@BISON@