diff --git a/squirrel/sqobject.cpp b/squirrel/sqobject.cpp
index 909e6e93..98cdcafa 100644
--- a/squirrel/sqobject.cpp
+++ b/squirrel/sqobject.cpp
@@ -11,6 +11,31 @@
 #include "sqclass.h"
 #include "sqclosure.h"
 
+const SQChar *SQMetaMethodName[] = {
+  _SC("_add"),
+  _SC("_sub"),
+  _SC("_mul"),
+  _SC("_div"),
+  _SC("_unm"),
+  _SC("_modulo"),
+  _SC("_set"),
+  _SC("_get"),
+  _SC("_typeof"),
+  _SC("_nexti"),
+  _SC("_cmp"),
+  _SC("_call"),
+  _SC("_cloned"),
+  _SC("_newslot"),
+  _SC("_delslot"),
+  _SC("_tostring"),
+  _SC("_newmember"),
+  _SC("_inherited"),
+  _SC("_shiftl"),
+  _SC("_shiftr"),
+  _SC("_and"),
+  _SC("_or"),
+  NULL
+};
 
 const SQChar *IdType2Name(SQObjectType type)
 {
@@ -46,6 +71,14 @@ const SQChar *GetTypeName(const SQObjectPtr &obj1)
     return IdType2Name(sq_type(obj1));
 }
 
+const SQChar *GetMetaMethodName(SQInteger mmId)
+{
+  if (mmId<MT_LAST)
+    return SQMetaMethodName[mmId];
+  else
+    return _SC("unknown");
+}
+
 SQString *SQString::Create(SQSharedState *ss,const SQChar *s,SQInteger len)
 {
     SQString *str=ADD_STRING(ss,s,len);
diff --git a/squirrel/sqobject.h b/squirrel/sqobject.h
index a2022227..c36ca53b 100644
--- a/squirrel/sqobject.h
+++ b/squirrel/sqobject.h
@@ -35,28 +35,14 @@ enum SQMetaMethod{
     MT_TOSTRING=15,
     MT_NEWMEMBER=16,
     MT_INHERITED=17,
-    MT_LAST = 18
+    MT_SHIFTL=18,
+    MT_SHIFTR=19,
+    MT_AND=20,
+    MT_OR=21,
+    MT_LAST = 22
 };
 
-#define MM_ADD      _SC("_add")
-#define MM_SUB      _SC("_sub")
-#define MM_MUL      _SC("_mul")
-#define MM_DIV      _SC("_div")
-#define MM_UNM      _SC("_unm")
-#define MM_MODULO   _SC("_modulo")
-#define MM_SET      _SC("_set")
-#define MM_GET      _SC("_get")
-#define MM_TYPEOF   _SC("_typeof")
-#define MM_NEXTI    _SC("_nexti")
-#define MM_CMP      _SC("_cmp")
-#define MM_CALL     _SC("_call")
-#define MM_CLONED   _SC("_cloned")
-#define MM_NEWSLOT  _SC("_newslot")
-#define MM_DELSLOT  _SC("_delslot")
-#define MM_TOSTRING _SC("_tostring")
-#define MM_NEWMEMBER _SC("_newmember")
-#define MM_INHERITED _SC("_inherited")
-
+extern const SQChar *SQMetaMethodName[];
 
 #define _CONSTRUCT_VECTOR(type,size,ptr) { \
     for(SQInteger n = 0; n < ((SQInteger)size); n++) { \
@@ -347,6 +333,7 @@ typedef sqvector<SQObjectPtr> SQObjectPtrVec;
 typedef sqvector<SQInteger> SQIntVec;
 const SQChar *GetTypeName(const SQObjectPtr &obj1);
 const SQChar *IdType2Name(SQObjectType type);
+const SQChar *GetMetaMethodName(SQInteger mmId);
 
 
 
diff --git a/squirrel/sqstate.cpp b/squirrel/sqstate.cpp
index 91826101..0e489d84 100644
--- a/squirrel/sqstate.cpp
+++ b/squirrel/sqstate.cpp
@@ -120,24 +120,8 @@ void SQSharedState::Init()
     newsysstring(_SC("instance"));
     newsysstring(_SC("bool"));
     //meta methods
-    newmetamethod(MM_ADD);
-    newmetamethod(MM_SUB);
-    newmetamethod(MM_MUL);
-    newmetamethod(MM_DIV);
-    newmetamethod(MM_UNM);
-    newmetamethod(MM_MODULO);
-    newmetamethod(MM_SET);
-    newmetamethod(MM_GET);
-    newmetamethod(MM_TYPEOF);
-    newmetamethod(MM_NEXTI);
-    newmetamethod(MM_CMP);
-    newmetamethod(MM_CALL);
-    newmetamethod(MM_CLONED);
-    newmetamethod(MM_NEWSLOT);
-    newmetamethod(MM_DELSLOT);
-    newmetamethod(MM_TOSTRING);
-    newmetamethod(MM_NEWMEMBER);
-    newmetamethod(MM_INHERITED);
+    for (int i=0; i<MT_LAST; i++)
+      newmetamethod(SQMetaMethodName[i]);
 
     _constructoridx = SQString::Create(this,_SC("constructor"));
     _registry = SQTable::Create(this,0);
diff --git a/squirrel/sqvm.cpp b/squirrel/sqvm.cpp
index 25249f65..297297f4 100644
--- a/squirrel/sqvm.cpp
+++ b/squirrel/sqvm.cpp
@@ -33,9 +33,23 @@ bool SQVM::BW_OP(SQUnsignedInteger op,SQObjectPtr &trg,const SQObjectPtr &o1,con
             case BW_USHIFTR:res = (SQInteger)(*((SQUnsignedInteger*)&i1) >> i2); break;
             default: { Raise_Error(_SC("internal vm error bitwise op failed")); return false; }
         }
+        trg = res;
+    }
+    else if( (sq_type(o1) & OT_INSTANCE) )
+    {
+        SQMetaMethod mm;
+        switch(op) {
+            case BW_AND:    mm = MT_AND; break;
+            case BW_OR:     mm = MT_OR;  break;
+            case BW_SHIFTL: mm = MT_SHIFTL; break;
+            case BW_SHIFTR: mm = MT_SHIFTR; break;
+            // add other
+            default: return false;
+        }
+        return ArithMetaMethod(mm,o1,o2,trg);
     }
     else { Raise_Error(_SC("bitwise op between '%s' and '%s'"),GetTypeName(o1),GetTypeName(o2)); return false;}
-    trg = res;
+
     return true;
 }
 
@@ -100,8 +114,20 @@ bool SQVM::ARITH_OP(SQUnsignedInteger op,SQObjectPtr &trg,const SQObjectPtr &o1,
             if(op == '+' && (tmask & _RT_STRING)){
                 if(!StringCat(o1, o2, trg)) return false;
             }
-            else if(!ArithMetaMethod(op,o1,o2,trg)) {
-                return false;
+            else
+            {
+              SQMetaMethod mm;
+              switch(op) {
+                case _SC('+'): mm=MT_ADD; break;
+                case _SC('-'): mm=MT_SUB; break;
+                case _SC('/'): mm=MT_DIV; break;
+                case _SC('*'): mm=MT_MUL; break;
+                case _SC('%'): mm=MT_MODULO; break;
+                case _SC('&'): mm=MT_AND; break;
+                case _SC('|'): mm=MT_OR;  break;
+                default:       mm=(SQMetaMethod)op;
+              }
+              if (!ArithMetaMethod(mm,o1,o2,trg)) return false;
             }
     }
     return true;
@@ -151,26 +177,16 @@ SQVM::~SQVM()
     REMOVE_FROM_CHAIN(&_ss(this)->_gc_chain,this);
 }
 
-bool SQVM::ArithMetaMethod(SQInteger op,const SQObjectPtr &o1,const SQObjectPtr &o2,SQObjectPtr &dest)
+bool SQVM::ArithMetaMethod(SQMetaMethod mm,const SQObjectPtr &o1,const SQObjectPtr &o2,SQObjectPtr &dest)
 {
-    SQMetaMethod mm;
-    switch(op){
-        case _SC('+'): mm=MT_ADD; break;
-        case _SC('-'): mm=MT_SUB; break;
-        case _SC('/'): mm=MT_DIV; break;
-        case _SC('*'): mm=MT_MUL; break;
-        case _SC('%'): mm=MT_MODULO; break;
-        default: mm = MT_ADD; assert(0); break; //shutup compiler
-    }
-    if(is_delegable(o1) && _delegable(o1)->_delegate) {
-
+    if(mm>=0 && mm<MT_LAST && is_delegable(o1) && _delegable(o1)->_delegate) {
         SQObjectPtr closure;
         if(_delegable(o1)->GetMetaMethod(this, mm, closure)) {
             Push(o1);Push(o2);
             return CallMetaMethod(closure,mm,2,dest);
         }
     }
-    Raise_Error(_SC("arith op %c on between '%s' and '%s'"),op,GetTypeName(o1),GetTypeName(o2));
+    Raise_Error(_SC("arith op %s on between '%s' and '%s'"), GetMetaMethodName(mm) ,GetTypeName(o1),GetTypeName(o2));
     return false;
 }
 
diff --git a/squirrel/sqvm.h b/squirrel/sqvm.h
index 50927507..b185c1a7 100644
--- a/squirrel/sqvm.h
+++ b/squirrel/sqvm.h
@@ -96,7 +96,7 @@ typedef sqvector<CallInfo> CallInfoVec;
 
     bool TypeOf(const SQObjectPtr &obj1, SQObjectPtr &dest);
     bool CallMetaMethod(SQObjectPtr &closure, SQMetaMethod mm, SQInteger nparams, SQObjectPtr &outres);
-    bool ArithMetaMethod(SQInteger op, const SQObjectPtr &o1, const SQObjectPtr &o2, SQObjectPtr &dest);
+    bool ArithMetaMethod(SQMetaMethod mm, const SQObjectPtr &o1, const SQObjectPtr &o2, SQObjectPtr &dest);
     bool Return(SQInteger _arg0, SQInteger _arg1, SQObjectPtr &retval);
     //new stuff
     _INLINE bool ARITH_OP(SQUnsignedInteger op,SQObjectPtr &trg,const SQObjectPtr &o1,const SQObjectPtr &o2);