diff --git a/openbsc/tests/gprs/Makefile.am b/openbsc/tests/gprs/Makefile.am
index e441259..904d567 100644
--- a/openbsc/tests/gprs/Makefile.am
+++ b/openbsc/tests/gprs/Makefile.am
@@ -1,4 +1,4 @@
-INCLUDES = $(all_includes) -I$(top_srcdir)/include
+AM_CPPFLAGS = $(all_includes) -I$(top_srcdir)/include
 AM_CFLAGS=-Wall -ggdb3 $(LIBOSMOCORE_CFLAGS) $(LIBOSMOGSM_CFLAGS)
 
 EXTRA_DIST = gprs_test.ok