diff --git a/src/proto/os_amiga.pro b/src/proto/os_amiga.pro
index b781680..7aaf171 100644
--- a/src/proto/os_amiga.pro
+++ b/src/proto/os_amiga.pro
@@ -15,6 +15,7 @@
 void mch_restore_title(int which);
 int mch_can_restore_title(void);
 int mch_can_restore_icon(void);
+void mch_setmouse(int on);
 int mch_get_user_name(char_u *s, int len);
 void mch_get_host_name(char_u *s, int len);
 long mch_get_pid(void);