diff --git a/fallback.c b/fallback.c
index f99fe63d..a41712cc 100644
--- a/fallback.c
+++ b/fallback.c
@@ -3,7 +3,7 @@
 ** TecCGraf - PUC-Rio
 */
  
-char *rcs_fallback="$Id: fallback.c,v 1.6 1994/11/16 17:38:08 roberto Exp roberto $";
+char *rcs_fallback="$Id: fallback.c,v 1.7 1994/11/18 19:46:21 roberto Exp roberto $";
 
 #include <stdio.h>
  
@@ -33,7 +33,6 @@ struct FB  luaI_fallBacks[] = {
 {"arith", {LUA_T_CFUNCTION, arithFB}},
 {"order", {LUA_T_CFUNCTION, orderFB}},
 {"concat", {LUA_T_CFUNCTION, concatFB}},
-{"unminus", {LUA_T_CFUNCTION, arithFB}},
 {"settable", {LUA_T_CFUNCTION, gettableFB}},
 {"gc", {LUA_T_CFUNCTION, GDFB}}
 };
diff --git a/fallback.h b/fallback.h
index d447ce04..33c22b0d 100644
--- a/fallback.h
+++ b/fallback.h
@@ -1,5 +1,5 @@
 /*
-** $Id: fallback.h,v 1.4 1994/11/10 17:36:54 roberto Exp roberto $
+** $Id: fallback.h,v 1.5 1994/11/18 19:46:21 roberto Exp roberto $
 */
  
 #ifndef fallback_h
@@ -18,9 +18,8 @@ extern struct FB {
 #define FB_ARITH  3
 #define FB_ORDER  4
 #define FB_CONCAT  5
-#define FB_UNMINUS  6
-#define FB_SETTABLE  7
-#define FB_GC 8
+#define FB_SETTABLE  6
+#define FB_GC 7
 
 void luaI_setfallback (void);
 int luaI_lock (Object *object);
diff --git a/opcode.c b/opcode.c
index d1869654..55a41ee1 100644
--- a/opcode.c
+++ b/opcode.c
@@ -3,7 +3,7 @@
 ** TecCGraf - PUC-Rio
 */
 
-char *rcs_opcode="$Id: opcode.c,v 3.17 1994/11/17 21:23:43 roberto Exp roberto $";
+char *rcs_opcode="$Id: opcode.c,v 3.18 1994/11/18 19:46:21 roberto Exp roberto $";
 
 #include <setjmp.h>
 #include <stdio.h>
@@ -989,7 +989,10 @@ static int lua_execute (Byte *pc, int base)
 
    case MINUSOP:
     if (tonumber(top-1))
-      do_call(&luaI_fallBacks[FB_UNMINUS].function, (top-stack)-1, 1, (top-stack)-1);
+    {
+      tag(top++) = LUA_T_NIL;
+      call_arith("unm");
+    }
     else
       nvalue(top-1) = - nvalue(top-1);
    break;