diff --git a/src/interfaces/ecpg/include/Makefile b/src/interfaces/ecpg/include/Makefile
index 5f59b7db89dd61b3971e28c78ea7161c32f742e7..6b9e39d1f3d6c4b4db53a6229c4243122adb21d7 100644
--- a/src/interfaces/ecpg/include/Makefile
+++ b/src/interfaces/ecpg/include/Makefile
@@ -5,7 +5,7 @@ include $(top_builddir)/src/Makefile.global
 install: all installdirs install-headers
 
 .PHONY: install-headers
-ecpg_headers = ecpgerrno.h ecpglib.h ecpgtype.h sqlca.h sql3types.h
+ecpg_headers = ecpgerrno.h ecpglib.h ecpgtype.h sqlca.h sql3types.h ecpg_informix.h
 install-headers: $(ecpg_headers)
 	for i in $^; do $(INSTALL_DATA) $$i $(DESTDIR)$(includedir); done