diff --git a/vcg/complex/algorithms/update/flag.h b/vcg/complex/algorithms/update/flag.h
index 3d258cba..83667988 100644
--- a/vcg/complex/algorithms/update/flag.h
+++ b/vcg/complex/algorithms/update/flag.h
@@ -245,7 +245,7 @@ static void FaceBorderFromVF(MeshType &m)
 					        vfi.f->Flags() |= BORDERFLAG[(vfi.z+2)%3];
           }
 			}	
-		VertexType::DeleteBitFlag(VertexType::LastBitFlag());
+		VertexType::DeleteBitFlag(visitedBit);
 }
 
  
diff --git a/vcg/connectors/hedge.h b/vcg/connectors/hedge.h
index 61506881..06af2230 100644
--- a/vcg/connectors/hedge.h
+++ b/vcg/connectors/hedge.h
@@ -141,34 +141,40 @@ public:
 	void SetV()		{this->Flags() |=VISITED;}
 	void ClearV()	{this->Flags() &=~VISITED;}
 	
-///  Return the first bit that is not still used
-static int &LastBitFlag()
-		{
-			static int b =USER0;
-			return b;
-		}
+	///  Return the first bit that is not still used
+	static int &FirstUnusedBitFlag()
+	{
+	  static int b =USER0;
+	  return b;
+	}
+
+	/// Allocate a bit among the flags that can be used by user. It updates the FirstUnusedBitFlag.
+	static inline int NewBitFlag()
+	{
+	  int bitForTheUser = FirstUnusedBitFlag();
+	  FirstUnusedBitFlag()=FirstUnusedBitFlag()<<1;
+	  return bitForTheUser;
+	}
+
+	/// De-allocate a pre allocated bit. It updates the FirstUnusedBitFlag.
+	// Note you must deallocate bit in the inverse order of the allocation (as in a stack)
+	static inline bool DeleteBitFlag(int bitval)
+	{
+	  if(FirstUnusedBitFlag()>>1==bitval) {
+		FirstUnusedBitFlag() = FirstUnusedBitFlag()>>1;
+		return true;
+	  }
+	  assert(0);
+	  return false;
+	}
 
-/// allocate a bit among the flags that can be used by user.
-static inline int NewBitFlag()
-		{
-			LastBitFlag()=LastBitFlag()<<1;
-			return LastBitFlag();
-		}
-// de-allocate a bit among the flags that can be used by user.
-static inline bool DeleteBitFlag(int bitval)
-		{	
-			if(LastBitFlag()==bitval) {
-					LastBitFlag()= LastBitFlag()>>1;
-					return true;
-			}
-			assert(0);
-			return false;
-		}
 	/// This function checks if the given user bit is true
 	bool IsUserBit(int userBit){return (this->Flags() & userBit) != 0;}
-	/// This function set  the given user bit 
+
+	/// This function set the given user bit
 	void SetUserBit(int userBit){this->Flags() |=userBit;}
-	/// This function clear the given user bit 
+
+	/// This function clear the given user bit
 	void ClearUserBit(int userBit){this->Flags() &= (~userBit);}
 
  template<class BoxType>
diff --git a/vcg/simplex/edge/base.h b/vcg/simplex/edge/base.h
index ad539421..c0c2f164 100644
--- a/vcg/simplex/edge/base.h
+++ b/vcg/simplex/edge/base.h
@@ -143,34 +143,40 @@ public:
 	void SetV()		{this->Flags() |=VISITED;}
 	void ClearV()	{this->Flags() &=~VISITED;}
 	
-///  Return the first bit that is not still used
-static int &LastBitFlag()
-		{
-			static int b =USER0;
-			return b;
-		}
+	///  Return the first bit that is not still used
+	static int &FirstUnusedBitFlag()
+	{
+	  static int b =USER0;
+	  return b;
+	}
+
+	/// Allocate a bit among the flags that can be used by user. It updates the FirstUnusedBitFlag.
+	static inline int NewBitFlag()
+	{
+	  int bitForTheUser = FirstUnusedBitFlag();
+	  FirstUnusedBitFlag()=FirstUnusedBitFlag()<<1;
+	  return bitForTheUser;
+	}
+
+	/// De-allocate a pre allocated bit. It updates the FirstUnusedBitFlag.
+	// Note you must deallocate bit in the inverse order of the allocation (as in a stack)
+	static inline bool DeleteBitFlag(int bitval)
+	{
+	  if(FirstUnusedBitFlag()>>1==bitval) {
+		FirstUnusedBitFlag() = FirstUnusedBitFlag()>>1;
+		return true;
+	  }
+	  assert(0);
+	  return false;
+	}
 
-/// allocate a bit among the flags that can be used by user.
-static inline int NewBitFlag()
-		{
-			LastBitFlag()=LastBitFlag()<<1;
-			return LastBitFlag();
-		}
-// de-allocate a bit among the flags that can be used by user.
-static inline bool DeleteBitFlag(int bitval)
-		{	
-			if(LastBitFlag()==bitval) {
-					LastBitFlag()= LastBitFlag()>>1;
-					return true;
-			}
-			assert(0);
-			return false;
-		}
 	/// This function checks if the given user bit is true
 	bool IsUserBit(int userBit){return (this->Flags() & userBit) != 0;}
-	/// This function set  the given user bit 
+
+	/// This function set the given user bit
 	void SetUserBit(int userBit){this->Flags() |=userBit;}
-	/// This function clear the given user bit 
+
+	/// This function clear the given user bit
 	void ClearUserBit(int userBit){this->Flags() &= (~userBit);}
 
  template<class BoxType>
diff --git a/vcg/simplex/face/base.h b/vcg/simplex/face/base.h
index 9f63333c..640144fa 100644
--- a/vcg/simplex/face/base.h
+++ b/vcg/simplex/face/base.h
@@ -206,34 +206,40 @@ public:
 	void ClearF(int i)	{this->Flags() &= (~(FAUX0<<i));}
 	void ClearAllF() { this->Flags() &= (~(FAUX0|FAUX1|FAUX2)); }
 	
-///  Return the first bit that is not still used
-static int &LastBitFlag()
-		{
-			static int b =USER0;
-			return b;
-		}
+	///  Return the first bit that is not still used
+	static int &FirstUnusedBitFlag()
+	{
+	  static int b =USER0;
+	  return b;
+	}
+
+	/// Allocate a bit among the flags that can be used by user. It updates the FirstUnusedBitFlag.
+	static inline int NewBitFlag()
+	{
+	  int bitForTheUser = FirstUnusedBitFlag();
+	  FirstUnusedBitFlag()=FirstUnusedBitFlag()<<1;
+	  return bitForTheUser;
+	}
+
+	/// De-allocate a pre allocated bit. It updates the FirstUnusedBitFlag.
+	// Note you must deallocate bit in the inverse order of the allocation (as in a stack)
+	static inline bool DeleteBitFlag(int bitval)
+	{
+	  if(FirstUnusedBitFlag()>>1==bitval) {
+		FirstUnusedBitFlag() = FirstUnusedBitFlag()>>1;
+		return true;
+	  }
+	  assert(0);
+	  return false;
+	}
 
-    /// allocate a bit among the flags that can be used by user.
-    static inline int NewBitFlag()
-		    {
-			    LastBitFlag()=LastBitFlag()<<1;
-			    return LastBitFlag();
-		    }
-    // de-allocate a bit among the flags that can be used by user.
-    static inline bool DeleteBitFlag(int bitval)
-		{	
-			if(LastBitFlag()==bitval) {
-					LastBitFlag()= LastBitFlag()>>1;
-					return true;
-			}
-			assert(0);
-			return false;
-		}
 	/// This function checks if the given user bit is true
 	bool IsUserBit(int userBit){return (this->Flags() & userBit) != 0;}
-	/// This function set  the given user bit 
+
+	/// This function set the given user bit
 	void SetUserBit(int userBit){this->Flags() |=userBit;}
-	/// This function clear the given user bit 
+
+	/// This function clear the given user bit
 	void ClearUserBit(int userBit){this->Flags() &= (~userBit);}
 
 
diff --git a/vcg/simplex/tetrahedron/base.h b/vcg/simplex/tetrahedron/base.h
index ee4ae5f6..3c236366 100644
--- a/vcg/simplex/tetrahedron/base.h
+++ b/vcg/simplex/tetrahedron/base.h
@@ -232,34 +232,40 @@ public:
 	/// This funcion execute the inverse operation of SetS()
 	void ClearB(int i)	{this->Flags() &= (~(BORDER0<<i));}
 	
-///  Return the first bit that is not still used
-static int &LastBitFlag()
-		{
-			static int b =USER0;
-			return b;
-		}
+	///  Return the first bit that is not still used
+	static int &FirstUnusedBitFlag()
+	{
+	  static int b =USER0;
+	  return b;
+	}
+
+	/// Allocate a bit among the flags that can be used by user. It updates the FirstUnusedBitFlag.
+	static inline int NewBitFlag()
+	{
+	  int bitForTheUser = FirstUnusedBitFlag();
+	  FirstUnusedBitFlag()=FirstUnusedBitFlag()<<1;
+	  return bitForTheUser;
+	}
+
+	/// De-allocate a pre allocated bit. It updates the FirstUnusedBitFlag.
+	// Note you must deallocate bit in the inverse order of the allocation (as in a stack)
+	static inline bool DeleteBitFlag(int bitval)
+	{
+	  if(FirstUnusedBitFlag()>>1==bitval) {
+		FirstUnusedBitFlag() = FirstUnusedBitFlag()>>1;
+		return true;
+	  }
+	  assert(0);
+	  return false;
+	}
 
-    /// allocate a bit among the flags that can be used by user.
-    static inline int NewBitFlag()
-		    {
-			    LastBitFlag()=LastBitFlag()<<1;
-			    return LastBitFlag();
-		    }
-    // de-allocate a bit among the flags that can be used by user.
-    static inline bool DeleteBitFlag(int bitval)
-		{	
-			if(LastBitFlag()==bitval) {
-					LastBitFlag()= LastBitFlag()>>1;
-					return true;
-			}
-			assert(0);
-			return false;
-		}
 	/// This function checks if the given user bit is true
 	bool IsUserBit(int userBit){return (this->Flags() & userBit) != 0;}
-	/// This function set  the given user bit 
+
+	/// This function set the given user bit
 	void SetUserBit(int userBit){this->Flags() |=userBit;}
-	/// This function clear the given user bit 
+
+	/// This function clear the given user bit
 	void ClearUserBit(int userBit){this->Flags() &= (~userBit);}
 
  template<class BoxType>
diff --git a/vcg/simplex/vertex/base.h b/vcg/simplex/vertex/base.h
index c8486db3..f4cb465c 100644
--- a/vcg/simplex/vertex/base.h
+++ b/vcg/simplex/vertex/base.h
@@ -190,34 +190,40 @@ public:
 	void SetV()		{this->Flags() |=VISITED;}
 	void ClearV()	{this->Flags() &=~VISITED;}
 	
-///  Return the first bit that is not still used
-static int &LastBitFlag()
-		{
-			static int b =USER0;
-			return b;
-		}
+	///  Return the first bit that is not still used
+	static int &FirstUnusedBitFlag()
+	{
+	  static int b =USER0;
+	  return b;
+	}
+
+	/// Allocate a bit among the flags that can be used by user. It updates the FirstUnusedBitFlag.
+	static inline int NewBitFlag()
+	{
+	  int bitForTheUser = FirstUnusedBitFlag();
+	  FirstUnusedBitFlag()=FirstUnusedBitFlag()<<1;
+	  return bitForTheUser;
+	}
+
+	/// De-allocate a pre allocated bit. It updates the FirstUnusedBitFlag.
+	// Note you must deallocate bit in the inverse order of the allocation (as in a stack)
+	static inline bool DeleteBitFlag(int bitval)
+	{
+	  if(FirstUnusedBitFlag()>>1==bitval) {
+		FirstUnusedBitFlag() = FirstUnusedBitFlag()>>1;
+		return true;
+	  }
+	  assert(0);
+	  return false;
+	}
 
-/// allocate a bit among the flags that can be used by user.
-static inline int NewBitFlag()
-		{
-			LastBitFlag()=LastBitFlag()<<1;
-			return LastBitFlag();
-		}
-// de-allocate a bit among the flags that can be used by user.
-static inline bool DeleteBitFlag(int bitval)
-		{	
-			if(LastBitFlag()==bitval) {
-					LastBitFlag()= LastBitFlag()>>1;
-					return true;
-			}
-			assert(0);
-			return false;
-		}
 	/// This function checks if the given user bit is true
 	bool IsUserBit(int userBit){return (this->Flags() & userBit) != 0;}
-	/// This function set  the given user bit 
+
+	/// This function set the given user bit
 	void SetUserBit(int userBit){this->Flags() |=userBit;}
-	/// This function clear the given user bit 
+
+	/// This function clear the given user bit
 	void ClearUserBit(int userBit){this->Flags() &= (~userBit);}
 
  template<class BoxType>