diff --git a/Makefile.am b/Makefile.am
index b0b0a6a..dada376 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -22,6 +22,7 @@
 ACLOCAL_AMFLAGS = -I m4
 
 MODULECOMMONFLAGS = -no-undefined -export-symbols-regex ".*" -shared -module -avoid-version
+MODULECOMMONCPPFLAGS = $(AM_CPPFLAGS)
 
 SUBDIRS = .