diff --git a/src/Makefile.am b/src/Makefile.am
index 92572d71..53535bf3 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -213,6 +213,7 @@ libmodsecurity_la_CPPFLAGS = \
 	$(GEOIP_CFLAGS) \
 	$(GLOBAL_CPPFLAGS) \
 	$(MODSEC_NO_LOGS) \
+	$(YAJL_CFLAGS) \
 	$(PCRE_CFLAGS)
 
 libmodsecurity_la_LIBADD = \