diff --git a/maildrop/maildrop/Makefile.in b/maildrop/maildrop/Makefile.in

index 9d921d4..b0ddee5 100644

--- a/maildrop/maildrop/Makefile.in

+++ b/maildrop/maildrop/Makefile.in

@@ -92,7 +92,7 @@ maildrop_LINK = $(LIBTOOL) --tag=CXX $(AM_LIBTOOLFLAGS) \

 	$(CXXFLAGS) $(maildrop_LDFLAGS) $(LDFLAGS) -o $@

 am_reformail_OBJECTS = reformail.$(OBJEXT)

 reformail_OBJECTS = $(am_reformail_OBJECTS)

-DEFAULT_INCLUDES = -I.@am__isrc@

+DEFAULT_INCLUDES = -I.@am__isrc@ -I$(includedir)/courier-authlib

 depcomp = $(SHELL) $(top_srcdir)/../depcomp

 am__depfiles_maybe = depfiles

 CXXCOMPILE = $(CXX) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) \