diff --git a/src/blua/lvm.c b/src/blua/lvm.c
index 46a015c1eb254bc86a59d726d041e5b6461e30d2..df0acb37ed3f8040d270aab3e27dec0e7c7a6490 100644
--- a/src/blua/lvm.c
+++ b/src/blua/lvm.c
@@ -541,11 +541,14 @@ void luaV_execute (lua_State *L, int nexeccalls) {
 	continue;
       }
       case OP_BNOT: {
-        TValue *rb = RB(i);
+        TValue *rb = RKB(i);
         if (ttisnumber(rb)) {
           lua_Number nb = nvalue(rb);
           setnvalue(ra, luai_numnot(nb));
         }
+        else if (ttisboolean(rb) || ttisnil(rb)) {
+          setbvalue(ra, l_isfalse(rb));
+        }
         else {
           Protect(Arith(L, ra, rb, rb, TM_NOT));
         }