diff --git a/extensions/Makefile.am b/extensions/Makefile.am
index e17628289..55f8e596a 100644
--- a/extensions/Makefile.am
+++ b/extensions/Makefile.am
@@ -1,4 +1,4 @@
-AM_CPPFLAGS = -I$(top_srcdir)/include -I$(top_srcdir)/libratbox/include
+AM_CPPFLAGS = -I$(top_srcdir)/include -I$(top_srcdir)/libratbox/include $(LTDLINCL)
 AM_LDFLAGS  = -module -export-dynamic -avoid-version -no-undefined -shared
 AM_LDFLAGS += -export-symbols-regex _mheader
 LIBS += $(top_srcdir)/libratbox/src/libratbox.la $(top_srcdir)/ircd/libircd.la
diff --git a/extensions/Makefile.in b/extensions/Makefile.in
index b8de33c5b..4191a8b44 100644
--- a/extensions/Makefile.in
+++ b/extensions/Makefile.in
@@ -585,7 +585,7 @@ target_alias = @target_alias@
 top_build_prefix = @top_build_prefix@
 top_builddir = @top_builddir@
 top_srcdir = @top_srcdir@
-AM_CPPFLAGS = -I$(top_srcdir)/include -I$(top_srcdir)/libratbox/include
+AM_CPPFLAGS = -I$(top_srcdir)/include -I$(top_srcdir)/libratbox/include $(LTDLINCL)
 AM_LDFLAGS = -module -export-dynamic -avoid-version -no-undefined \
 	-shared -export-symbols-regex _mheader
 extensiondir = @moduledir@/extensions
diff --git a/modules/Makefile.am b/modules/Makefile.am
index 93940acd8..413a792ca 100644
--- a/modules/Makefile.am
+++ b/modules/Makefile.am
@@ -1,6 +1,6 @@
 AUTOMAKE_OPTIONS = subdir-objects
 
-AM_CPPFLAGS = -I$(top_srcdir)/include -I$(top_srcdir)/libratbox/include
+AM_CPPFLAGS = -I$(top_srcdir)/include -I$(top_srcdir)/libratbox/include $(LTDLINCL)
 AM_LDFLAGS  = -module -export-dynamic -avoid-version -no-undefined -shared
 AM_LDFLAGS += -export-symbols-regex _mheader
 LIBS += $(top_srcdir)/libratbox/src/libratbox.la $(top_srcdir)/ircd/libircd.la
diff --git a/modules/Makefile.in b/modules/Makefile.in
index 526d064ef..492b47710 100644
--- a/modules/Makefile.in
+++ b/modules/Makefile.in
@@ -652,7 +652,7 @@ top_build_prefix = @top_build_prefix@
 top_builddir = @top_builddir@
 top_srcdir = @top_srcdir@
 AUTOMAKE_OPTIONS = subdir-objects
-AM_CPPFLAGS = -I$(top_srcdir)/include -I$(top_srcdir)/libratbox/include
+AM_CPPFLAGS = -I$(top_srcdir)/include -I$(top_srcdir)/libratbox/include $(LTDLINCL)
 AM_LDFLAGS = -module -export-dynamic -avoid-version -no-undefined \
 	-shared -export-symbols-regex _mheader
 auto_load_moddir = @moduledir@/autoload