diff --git a/src/classes/Makefile.am b/src/classes/Makefile.am
index 16ede5e0..f6c13d5d 100644
--- a/src/classes/Makefile.am
+++ b/src/classes/Makefile.am
@@ -91,7 +91,7 @@ AM_LDFLAGS = $(LOCAL_LIB_LDFLAGS) -L@ROOTLIBDIR@
 CLEANFILES = *Dict.cpp *Dict.h *~ core
 
 %Dict.cpp %Dict.h: ../include/%.h ../include/%LinkDef.h
-	@ROOTCINT@ -v -f $*Dict.cpp -c -p $(INCLUDES) $^
+	@ROOTCINT@ -v -f $*Dict.cpp -c -p $(AM_CPPFLAGS) $^
 
 lib_LTLIBRARIES = libPUserFcnBase.la libPMusr.la