Does anyone know how to change the start button image through some API call?

I manage to get the Start Button handle, but fail to change the image... enclose is the sample code

PHP Code:
    HWND    hWnd=NULL;
    
HBITMAP    hBitmap=NULL;
    
long    x=0;

    
hWnd FindWindow("Shell_TrayWnd",NULL);
    if (
hWnd != NULL)
    {
        
hWnd FindWindowEx(hWndNULL"Button"NULL);
        if (
hWnd != NULL)
        {
            
hBitmap static_cast<HBITMAP>(LoadImage(hInst, (LPCTSTR)IDB_MYBUTTONIMAGE_BITMAP00LR_DEFAULTSIZE));
            
SendMessage(hWndBM_SETIMAGEIMAGE_BITMAP, (LPARAM)hBitmap);        
        }
    } 
regaards,