diff --git a/src/Makefile.am b/src/Makefile.am
index 2ae43b03..a6489dfd 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -260,4 +260,4 @@ if TUNEMU
 LIBS += -lpcap
 endif
 
-AM_CFLAGS = -DCONFDIR=\"$(sysconfdir)\" -DLOCALSTATEDIR=\"$(localstatedir)\" -DSBINDIR=\"$(sbindir)\" -I.
+AM_CFLAGS = -DCONFDIR=\"$(sysconfdir)\" -DLOCALSTATEDIR=\"$(localstatedir)\" -DSBINDIR=\"$(sbindir)\" -iquote.