diff --git a/ltm.c b/ltm.c
index 7f6ebc63..aaba8943 100644
--- a/ltm.c
+++ b/ltm.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ltm.c,v 1.89 2002/04/05 18:54:31 roberto Exp roberto $
+** $Id: ltm.c,v 1.90 2002/04/30 13:01:48 roberto Exp roberto $
 ** Tag methods
 ** See Copyright Notice in lua.h
 */
@@ -47,7 +47,7 @@ void luaT_init (lua_State *L) {
 const TObject *luaT_gettm (Table *events, TMS event, TString *ename) {
   const TObject *tm = luaH_getstr(events, ename);
   if (ttype(tm) == LUA_TNIL) {  /* no tag method? */
-    events->flags |= (1<<event);  /* cache this fact */
+    events->flags |= (1u<<event);  /* cache this fact */
     return NULL;
   }
   else return tm;
diff --git a/ltm.h b/ltm.h
index eedcc32d..ab6c375a 100644
--- a/ltm.h
+++ b/ltm.h
@@ -1,5 +1,5 @@
 /*
-** $Id: ltm.h,v 1.1 2001/11/29 22:14:34 rieru Exp rieru $
+** $Id: ltm.h,v 1.31 2002/01/09 21:50:35 roberto Exp roberto $
 ** Tag methods
 ** See Copyright Notice in lua.h
 */
@@ -35,7 +35,7 @@ typedef enum {
 
 
 #define fasttm(l,et,e) \
-  (((et)->flags & (1<<(e))) ? NULL : luaT_gettm(et, e, G(l)->tmname[e]))
+  (((et)->flags & (1u<<(e))) ? NULL : luaT_gettm(et, e, G(l)->tmname[e]))
 
 
 const TObject *luaT_gettm (Table *events, TMS event, TString *ename);