Problem in BitBlt Function

Code for the program is :

#include "StdAfx.h"
#include "resource.h"
#include ".\chidmenu.h"
#define mnuHeight 24
#define mnuWidth 163

CChidMenu::CChidMenu(void)
{
}

CChidMenu::~CChidMenu(void)
{
}

void CChidMenu ::DrawItem (LPDRAWITEMSTRUCT lpDIS)
{
   if(lpDIS->itemAction == ODA_DRAWENTIRE)
   {
        DrawEntireMenu(lpDIS);
   }
   //if()
}

void CChidMenu ::DrawEntireMenu (LPDRAWITEMSTRUCT lpDIS)
{
    CDC* pDC = CDC::FromHandle(lpDIS->hDC);

    CDC *tempDC=new CDC();
    tempDC->CreateCompatibleDC (pDC);
    CBitmap bmpMenuBitamp,*oldBitmap;
    BOOL b=bmpMenuBitamp.LoadBitmap (IDB_BITMAP2);
    oldBitmap=tempDC->SelectObject (&bmpMenuBitamp);
    pDC->BitBlt (0,0,mnuWidth,3*mnuHeight,tempDC,0,0,SRCCOPY);

}
void CChidMenu::MeasureItem(LPMEASUREITEMSTRUCT MenuMeasurement)
{
    MenuMeasurement->itemHeight =mnuHeight;
    MenuMeasurement->itemWidth =mnuWidth ;
}

Output:

There is a difference in the bitmap ... border and the CDC border....
it becomes visible that ...somthing is pasted...on the CDC n there is
difference in all the 4 corners...

How to remove the difference ...? Is the ... Menu CDC gives less
area...to paint??
Help needed