diff --git a/ggsn/Makefile.am b/ggsn/Makefile.am
index 906077f..761c820 100644
--- a/ggsn/Makefile.am
+++ b/ggsn/Makefile.am
@@ -1,8 +1,8 @@
 bin_PROGRAMS = ggsn
 
-LDFLAGS = @EXEC_LDFLAGS@
+AM_LDFLAGS = @EXEC_LDFLAGS@
 
-CFLAGS = -O2 -D_GNU_SOURCE -fno-builtin -Wall -DSBINDIR='"$(sbindir)"' -ggdb
+AM_CFLAGS = -O2 -D_GNU_SOURCE -fno-builtin -Wall -DSBINDIR='"$(sbindir)"' -ggdb
 
 ggsn_LDADD = @LIBOBJS@ @EXEC_LDADD@ -lgtp -L../gtp