diff --git a/Makefile b/Makefile
index b293775f1f..f9a0de0816 100644
--- a/Makefile
+++ b/Makefile
@@ -64,6 +64,8 @@ export CURSES_DIR
 export NCURSES_DIR
 export TERMCAP_DIR
 export TINFO_DIR
+export GTK2_LIB
+export GTK2_INCLUDE
 
 # even though we could use '-include makeopts' here, use a wildcard
 # lookup anyway, so that make won't try to build makeopts if it doesn't