diff --git a/src/libcharon/plugins/farp/Makefile.am b/src/libcharon/plugins/farp/Makefile.am
index 6da64509f..42cd31879 100644
--- a/src/libcharon/plugins/farp/Makefile.am
+++ b/src/libcharon/plugins/farp/Makefile.am
@@ -1,5 +1,6 @@
 
-INCLUDES = -I$(top_srcdir)/src/libstrongswan -I$(top_srcdir)/src/libcharon
+INCLUDES = -I$(top_srcdir)/src/libstrongswan -I$(top_srcdir)/src/libhydra \
+	-I$(top_srcdir)/src/libcharon
 
 AM_CFLAGS = -rdynamic