diff --git a/exposed/Makefile.am b/exposed/Makefile.am
index 757b378..bb80b3d 100644
--- a/exposed/Makefile.am
+++ b/exposed/Makefile.am
@@ -1,5 +1,7 @@
 ## exposed/Makefile.am
 
+AUTOMAKE_OPTIONS = subdir-objects
+
 AM_CPPFLAGS = -DLIBRARY -I$(top_srcdir)/src
 
 AM_LDFLAGS = -L.
diff --git a/src/Makefile.am b/src/Makefile.am
index 13bb621..eda11fb 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1,5 +1,7 @@
 ## src/Makefile.am
 
+AUTOMAKE_OPTIONS = subdir-objects
+
 AM_CPPFLAGS = $(FLTK_CXXFLAGS) $(LIBSPNAV_CPPFLAGS)
 
 if WIN32