diff --git a/crypto/Makefile.am b/crypto/Makefile.am
index c9c132d..d72e182 100644
--- a/crypto/Makefile.am
+++ b/crypto/Makefile.am
@@ -2,6 +2,7 @@ include $(top_srcdir)/Makefile.am.common
 
 AM_CPPFLAGS += -I$(top_srcdir)/crypto/asn1
 AM_CPPFLAGS += -I$(top_srcdir)/crypto/bn
+AM_CPPFLAGS += -I$(top_srcdir)/crypto/ec
 AM_CPPFLAGS += -I$(top_srcdir)/crypto/evp
 AM_CPPFLAGS += -I$(top_srcdir)/crypto/modes
 AM_CPPFLAGS += -I$(top_srcdir)/crypto